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The owners of The Right Sort Marriage Bureau are back, and more determined than ever to bring love matches to the residents of Post-WWII London . . . so something as trivial as being dragged into a spy mission isn’t going to stop them!

Sparks fly when an old friend comes to town . . .

London, 1947. After recent events have left the normally steadfast Iris Sparks thoroughly shaken, she’s looking forward to some peace. With The Right Sort doing well, she and business partner Gwen Bainbridge are due a holiday. Until Iris’s former boss enlists their help for a secret mission.

Iris, who left British intelligence after the war, is being recruited for her Cambridge connection to one Anthony Danforth. She hasn’t seen Tony in almost ten years, yet she and Gwen must manipulate him into hiring their marriage service.

Tony’s suspected of being a Soviet operative, and an undercover agent posing as his perfect match could discover the truth. Despite her reluctance at being dragged back into the world of espionage, Iris agrees. After all, Tony was once a very good friend. If he’s innocent, she’ll happily prove it. If not? Well, no one ever said being a spy was easy . . .

Those who enjoy reading Kerry Greenwood's Phryne Fisher Mysteries and Dorothy Sayers will adore this warm and witty historical mystery!

256 pages, Hardcover

First published January 6, 2026

37 people are currently reading
477 people want to read

About the author

Allison Montclair

14 books519 followers
ALLISON MONTCLAIR grew up devouring hand-me-down Agatha Christie paperbacks and James Bond movies. As a result of this deplorable upbringing, Montclair became addicted to tales of crime, intrigue, and espionage. She now spends her spare time poking through the corners, nooks, and crannies of history, searching for the odd mysterious bits and transforming them into novels of her own. The Right Sort of Man is her debut novel.

Allison Montclair is a pseudonym of Alan Gordon.

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Displaying 1 - 30 of 84 reviews
Profile Image for Valleri.
1,023 reviews47 followers
November 12, 2025
The Fire Must Burn is #8 in the Sparks and Bainbridge Mystery Series. The story is set in post-WWII London in 1947 and features protagonists Iris Sparks and Gwen Bainbridge, who run a marriage bureau. In this installment, Iris is asked by British Intelligence to use her and Gwen's matchmaking services to investigate a former friend suspected of being a Soviet agent.

I loved this book! How did I not know about this series?? The period detail felt spot-on, the pace was fast, and the bits of humor were enjoyable! Iris Sparks and Gwen Bainbridge share a friendship that is both believable and heart-warming. This time out, we follow this daring duo, who are owners of The Right Sort Marriage Bureau. Iris's former boss from British intelligence enlists their help for a secret mission. They must manipulate an old friend of Iris's, Anthony Danforth, into using their marriage service so that an undercover agent can investigate if he is a Soviet operative.

I highly recommend The Fire Must Burn!

Huge thanks to #SevernHouse for providing this book for review and consideration via #NetGalley. All opinions are my own. The Fire Must Burn has an expected publication date of January 6, 2026.

#AllisonMontclair #Friendship #Espionage #Mystery #Suspense #Series
Profile Image for Laura Hill.
1,003 reviews85 followers
October 5, 2025
Thank you to Severn House and NetGalley for providing an advance copy of this book in exchange for my honest review. The book will be published on January 6th, 2026.

Book 8 of the Sparks and Bainbridge historical mystery series, and definitely my favorite so far. London, 1947, and the co-owners of The Right Sort Marriage Bureau are being asked to do a “favor” for British Intelligence by using their matching services to determine whether one Anthony Danforth is or is not a Soviet agent. The catch is that Iris Sparks — once in British Intelligence herself — had been a good friend of Danforth’s back in their Cambridge days, though it has been over a decade since they had seen each other. The plot thickens further with an “almost” body, some clashing secrets, and ongoing doubts as to the ethics of their subterfuge.

I like the series for the snappy writing, the deep and personal historical contexts, and the two main characters — each unusual for their time, but also squarely OF their time. Both serve as exemplars of how times were changing for women, and some of the means by which women were bringing that change about. In this particular installment, I particularly enjoyed the slowly elaborated 1935 Cambridge story that set the stage for the present day mystery. This was full of details — both political and cultural — that helped me understand what life was like in that era. I also liked the various (and plentiful) ethical dilemmas that peppered the plot — presented thoughtfully and resolved (as one often must when one lives in reality) in practical, rather than wholly principled ways.

Intellectually engaging, little to no filler, and thoroughly enjoyable.
Profile Image for Literary Redhead.
2,760 reviews702 followers
September 28, 2025
A unique and intriguing histfic mystery involving the owners of The Right Source Marriage Bureau in England in 1947, still intent on serving as matchmakers for Londoners despite being pulled into a post-war spy investigation. Loved it!
Profile Image for eyes.2c.
3,126 reviews111 followers
January 14, 2026
Another sturdy mystery from our Right Sort Marriage Bureau Dames!

Iris Sparks and Gwendolyn Bainbridge once more delight with their savoire fare attitude to life, secret service personnel confrontations, ability to bend the rules, and solve mysteries
Iris has been dealt a heartfelt blow with the death of Archie, and is still hurting.
The war has ended, but for the Brigadier this is the perfect time for his passion to route out any communist sympathisers who might be betraying Britain in the new Cold War frontiers to come to the fore.
A trip down memory lane for Iris and her rowing Cambridge years evoke thoughts of her first introduction to Anthony Danforth in her Newman College years. The Brigadier suspects Tony of being a double agent. He wants the Right Sort Marriage Bureau to take Tony on as a client. He already has an agent lined up to be a perspective bride.
Iris and Gwen are the Brigadier’s not so perfect agents! This time they tread a narrow path between being possibly imprisoned and getting to the truth. A truth that has its roots in Iris’ Cambridge days.
A look into both ladies’ past and present that deepens our understandings of them.
What a pleasure!

A Severn ARC via NetGalley.
Many thanks to the author and publisher.
Profile Image for Dawn Michelle.
3,124 reviews
February 7, 2026
This was by far my favorite of the series; Gwen and Iris are reminders of all that women went through to get us where we are right now and how much work we STILL have to do for those who are coming up after us.

The story is very good, yet also very sad- you can believe that somewhere, at that time, something like this happened [because it did AND does happen all the time]. The mystery was okay [I guessed the twist early on, but not the exact why], but after awhile, its not really about a mystery but really about hurting those we love, losing loved ones, and trying to eventually heal.

MUCH more introspective than the previous books, this one will make you think, make you weep for those who lost so much, want your loved ones closer [HUG THOSE YOU LOVE. TELL THEM YOU LOVE THEM], will make you want those who do very bad things held accountable [RELEASE THE FULL EPSTEIN FILES!] , and I guarantee, will stay with you for a very long time.

Thank you to NetGalley, Allison Montclair, and Severn House for providing this ARC in exchange for an honest review.
Profile Image for Donna.
1,044 reviews46 followers
January 21, 2026
I would give it more stars if I could!! This installment finds Sparks and Bainbridge helping out Sparks old boss see if a former employee is a double agent by setting him up with someone through their agency. But it becomes a lot more that anyone bargained for when he is almost murdered with a Molotov cocktail. Really great story!!
Profile Image for Kelly.
63 reviews3 followers
January 13, 2026
Well, this was another fun adventure from author Alison Montclair. The duo of Sparks and Bainbridge join forces again in crime fighting, and continue to make matches in their business of finding love for others. But past intelligence work and clients with dangerous pasts interfere with an easy going approach. The book jumps between two timelines, one of which is right before WWII, and involves Iris’ friends from Cambridge, and one is the their current time, about 1957.
One of the past friends has just returned from abroad and reconnected with Sparks. She is asked by Intelligence to introduce him to another operative in order to discover if he is a double agent. However, he ends up being attacked, and now multiple agencies are investigating. It was a solid plot, just didn’t grab me like some. However, I do recommend it if you enjoy historical mystery.
Thank you to NetGalley and publisher for an advance copy. Opinions are my own.
273 reviews
January 25, 2026
2.5 stars. Well, this was disappointing. The theme and tone of this book was not what I expected from a Sparks & Bainbridge book. Midway through I wondered if a different author was writing it. There was zero charm at all and it was very dark in nature. The highlight was the rowing competition and Sparks on the narrowboat. After eight books, I won't be continuing on.
1,242 reviews31 followers
January 6, 2026
Gwen Bainbridge and Iris Sparks are as different as night and day, but together they are a formidable team. Gwen is a widow with a young son. She is from a wealthy family with aristocratic connections. Iris comes from the working class, attended Cambridge and worked for British Intelligence during the war. When the two became friends they recognized a need after the war and opened a marriage bureau. Iris is contacted by her former commander and is given no choice but to take on a mission. Tony Danforth, a friend from her Cambridge days, has recently returned from China to take a position with the Foreign Office. He is suspected of being a Soviet agent. Iris and Gwen must persuade him to use their company to find a wife, a benefit in his profession. Intelligence will provide an agent for the match, whose assignment is to discover the truth. Enter Evelyn Lowle. She is a new agent trying to prove herself and immediately sets Iris, a veteran agent, on edge. Her first date with Tony is successful. Before they can connect for a second date Tony’s apartment is fire bombed and he is critically injured. Iris and Gwen are determined to discover who was responsible, taking Iris back to her Cambridge days and an event that led to the death of a friend.

In 1938 Tony and Iris spent a weekend on an estate with their friends Keith, Bruce and Nancy. Screams woke Iris in the middle of the night. Nancy was being consoled by the housekeeper and was gone by morning. Back at school she refused to see Iris and later committed suicide. By the end of the war Kevin and Bruce were dead, Tony was in China and Iris never discovered what happened that night. While the police investigate the attack on Tony, Gwen uses her contacts in society to trace the boys’ families and the housekeeper. When she and Iris discover a connection to their current Intelligence mission they are bound by the Official Secrets Act. Tony is still in danger, but they are unable to share what they discovered with the police. It is up to Gwen and Iris to find a solution to keep him safe. Allison Montclair’s story takes you to a London that is still recovering from the war. She takes you from the country estates to central London, with its’ pubs and river boats. The banter between Gwen and Iris flows naturally and there is a genuine friendship between them. This has become one of my favorite series and is highly recommended. I would like to thank NetGalley and Severn House Publishing for providing this book.
Profile Image for Emily Gawlak.
128 reviews7 followers
January 2, 2026
Absolutely fantastic! I’m find myself rather speechless since finishing Fire Must Burn. The entire story was so enthralling and breathtaking, that I didn’t want it to end. The Sparks and Bainbridge series draws you in and doesn’t let you go, it always leaves you wanting more.

I keep flipping Fire Must Burn over in my mind and I just can’t get over how good it was. I will say, The Sparks and Bainbridge series is one I continue to think about periodically, just pouring over the various books because I can never seem to get enough of it. I simply love the series.

I highly recommend the Audiobooks, I listen to them in order multiple times a year. I highly recommend them.

I highly recommend Fire Must Burn, and the entire Sparks and Bainbridge series, it is positively addictive! Fire Must Burn was the perfect first read of the new year!

Until next time,
Happy Reading! 📖
Profile Image for Catherine Woodman.
5,963 reviews118 followers
February 19, 2026
This installment in one of my favorite murder mystery series does some back story work on Sparks. It is very solid, if with a different angle, going back to what Sparks did during the war. It also involves the cover up of a sexual assault, which is very much in the news these days, with the extensively redacted records of a convicted sexual predator having been recently released.
Profile Image for Mary .
111 reviews2 followers
February 12, 2026
One of my favorite fiction series just provide a compelling story and an unexpected conclusion. I think this has been the best yet of Montclair’s storytelling . Cannot wait for the next installment.
Profile Image for Siouxsie.
217 reviews3 followers
February 2, 2026
3 1/2 stars. This series is getting darker.
Profile Image for Marlene.
3,473 reviews244 followers
February 6, 2026
This series began with The Right Sort of Man about two women opening a marriage bureau in post-World War II London. Miss Iris Sparks, formerly something seriously clandestine during the late war, and Mrs. Gwendoline Bainbridge, formerly a resident of a sanatorium after the death of her husband and the loss of what would have been her second child, start their agency because they both need jobs. Gwen needs to focus on her recovery so can legally reclaim her sanity and independence and regain custody of her remaining son. Iris, so she can pay the rent. They are not from the same social class but they quickly learn that their own weaknesses are the other’s strengths.

Strength they both need when one of their first clients is charged with murdering one of the others.

By this point in the series, now eight books in, Sparks and Bainbridge are ride or die friends and partners, and the tables have sort of turned on the dynamics of their friendship/sisterhood. Sparks is recovering from the loss of her gangster lover, she’s houseboat sitting in lieu of getting her own apartment, and she’s at a low point, just ripe for manipulation by her old boss/spymaster. Bainbridge has reclaimed her legal rights to her life and her remaining child, she’s in the midst of a new romance, and has just signed the Official Secrets Act because Sparks has let too many cats out of too many bags that should have been kept firmly shut in order to save both of them from the consequences of some of their more dangerous cases.

Which puts Sparks and Bainbridge squarely into – or back into in Sparks’ case – the spy game. Not against Britain’s wartime enemies, but against the new enemies all around them. It’s 1947 and one of Sparks’ old friends from Cambridge is suspected of being a Communist. (The UK and the US were seeing communists under every hedgerow in the post-war period, which gave rise to McCarthyism and the “Red Scares” of the 1950s in the US.)

It’s also true that a lot of young people, particularly college students, flirted with both socialism and communism in the 1930s, between the wars and during the Great Depression. And some became communist agents before, during and after the war. A particularly infamous spy ring, the Cambridge Five, was uncovered in the 1950s.

However, this story takes place in 1947, and the Cambridge Five have not been uncovered yet. But Sparks’ friend Tony Danforth, and for that matter, Sparks herself, did flirt with both political movements in their Cambridge days in the mid-1930s. Sparks definitively turned away, the question that the Brigadier needs to answer is whether or not Danforth did as well. His plan is to use Sparks, Bainbridge and the Right Sort Marriage Bureau as a kind of honeytrap for Danforth.

It’s not going to work the way that the Brigadier thinks it will. He’s correct that Danforth is keeping a secret, but he’s very, very wrong about the nature of the secret that Danforth is keeping. Not that he cares. But Sparks and Bainbridge very much do.

Escape Rating A: I’ve been reading this series from its opening in The Right Sort of Man, and have enjoyed every single one. But the tone of the series has changed over the course of those eight books, and the covers tell their own story. The first two covers were a bit soft-focused and reflected the romances that “The Right Sort” Marriage Bureau was working to create. Not that a murder didn’t occur, and not that the plot beats of a murder investigation didn’t drive both stories, but they were sorta/kind cozies – albeit with a more than a few twists.

The next several books, from A Rogue’s Company to Murder at the White Palace, look more like romantic suspense covers, which also represents one facet of those stories. It’s clear just from the covers that Sparks and Bainbridge are in a LOT more danger in those stories, and not just as a result of Sparks’ romance with gangleader Archie Spelling. If you compare the original version of the cover of A Rogue’s Company with the current version (both at left), that turn is made very manifest between the two.

The covers for the previous book, An Excellent Thing in a Woman, and this one, Fire Must Burn, represent another turn. They may be labelled as mysteries, but those are thriller covers, and so they should be. The Cold War is heating up – so to speak – and Iris Sparks and Gwen Bainbridge, both now signatories of the Official Secrets Act, are in the spy game up to their necks as a result of favors owed to Iris’ wartime boss, the mysterious Brigadier. Who is obviously a high-muckety-muck of one sort or another in MI6.

(I recognize that this series also experienced a change in publishers between Murder at the White Palace and An Excellent Thing in a Woman, but have no way of unraveling the reasons behind that ball of wax. I just see that the new covers EXCELLENTLY fit the new direction.)

This eighth entry in the series is a story about youthful folly, the power of privilege, the distribution of collateral damage and the price of consequences. And it kept me glued to my seat from beginning to end.

There were multiple strands to that glue. The story operates in two timelines, Sparks’ and Bainbridge’s 1947 present, AND Sparks’ own mid 1930s past at Cambridge. There are fascinating reveals in both timelines, with a kind of how it started vs. how it’s going feel. Sparks was a barely middle-class female student at Cambridge in the 1930s, and we see her as young, foolish, risk-taking and rule-breaking in a way that both fits with who we know AND shows how far she’s come as well as how the war and her own losses have changed her.

All of which are set in sharp contrast by the young female agent the Brigadier sends to seduce Danforth. A young woman very much like Sparks used to be, reminding her that she’s now 30 and scarred and jaded by her experiences. Especially the experience that set her on the course she is currently on – for both good and ill.

The story concludes with a whole lot of surprising reveals – not so much the whodunnits as a bunch of whydunnits all around. More importantly for both Sparks and Bainbridge, an all too intimate view of the changed nature of what seemed righteous in wartime but has now become a very dirty and dangerously clandestine war. One where not even the supposed “good guys” give a good goddamn about the cost – not even to their own.

It’s clear that Sparks is going to have to find a way to extricate herself and Bainbridge from the mess that necessity and expediency have gotten them into. The question is whether the Brigadier and MI6 will be willing to let them go.

A burning question – possibly literally – for the next book in the series. Hopefully this time next year.

Originally published at Reading Reality
Profile Image for Kat.
1,049 reviews43 followers
Review of advance copy received from Netgalley
December 31, 2025
Fire Must Burn is Book 8 of A Sparks and Bainbridge Mystery series by Allison Montclair. I stumbled upon this series when I started to read historical mysteries, so I thought I'd give it a try. I was immediately hooked! I've now read books 3, 5, 6, 7 and now 8 of the series. I desperately need to read those that I missed; I must find them in my virtual towering TBR pile. Each of the mysteries stand alone, but you will want to see the progression of the characters. But jump right in even if it's your first. I promise you will LOVE these characters!

In London, 1947, recent events have left the normally steadfast Iris Sparks seriously shaken. Some peace and quiet would be good about now. With The Right Sort doing well, she and business partner Gwen Bainbridge need some downtime. However, Iris’s former boss enlists their help for a secret mission. Iris, who left British intelligence after the war, is being recruited due to her Cambridge connection to Anthony Danforth. She hasn’t seen Tony in almost ten years, but she and Gwen must manipulate him into hiring their marriage service. Tony’s suspected of being a Soviet operative, and an undercover agent posing as his perfect match could discover the truth. Despite her reluctance being dragged back into the world of espionage, Iris agrees. After all, Tony was once a very good friend. If he’s innocent, she’ll happily prove it. If he isn't, well...no one said being a spy was easy!

Book 7 of the series broke my heart and had me bawling like a baby! I have grown to love the characters in this series, and I greatly feel the loss of a particular character. Yet I knew I MUST continue on with Iris Sparks and Gwen Bainbridge. The stories are fascinating, but these characters keep me coming back for more. Not only does this book concern espionage, but it is also a testament to female friendship. Guys, don't let that scare you off! You will enjoy the characters' relationship as much as we women do. Iris and Gwen are extremely different and are unlikely friends. Iris was a spy during World War II, and she doesn't much care for being pulled back into that life. She and Gwen are the owners and operators of The Right Sort Marriage Bureau. Quite different than being a spy! Iris never met a drink she didn't like. She lost someone she cared deeply about, and she lives on a long boat when she's not working. I learned in this book that she loved "beetling". Yes, Iris is fascinated with beetles. (Gwen asked were they sort of like "aquatic cockroaches". Ha!) Then we have Gwen. She lost her husband in the war, and went a bit crazy, She's in a wealthy family, but lost custody of her son because of her breakdown. She now has custody of son Ronnie again, and is dating Sally, who is Iris's best friend. These disparate women have come to be dear friends, and not in a sappy way. This particular case was fascinating, Iris being forced to determine if a good friend of her from 10 years ago was now a Soviet operative. If that wasn't bad enough, they had to use The Right Sort as a way of discovering if Tony has any secrets. Iris and Gwen were also trying to figure out what. happened to cause the death of a Cambridge student and friend all those years ago. This is a serious story, but I find myself laughing out loud a lot...these women can be really funny! Tony was an interesting character, and boy, did he have a big problem here. I just adore supporting character Sally Danielli. Gwen leaves The Right Sort at lunch to "visit" Sally. He is extremely tall, and some people's reaction to that are amusing. I am extremely fond of these characters; I hope Iris and Gwen have many more books ahead...I would miss their friendship and their great adventures if this series came to a close. I hope it doesn't happen for a long, long time!

I received an ARC of this book courtesy of the publisher and NetGalley. I received no compensation for my review, and all thoughts and opinions expressed are entirely my own.
Reviews PublishedFrequently Auto-ApprovedProfessional ReaderCamp NetGalley 2024500 Book Reviews
14 reviews1 follower
January 8, 2026
This is book 8 of a series following Iris Sparks and Gwen Bainbridge in their adventures solving mysteries and running the Right Sort Marriage Bureau (a matchmaking service) in the immediate aftermath of WWII. This story covers the duo's investigations into a "cold case" college mystery involving the death of a friend of Iris and the current investigations of another college friend of Iris. The latter mission also involves some of Iris' British Intelligence contacts. We find out more about Iris' past though I would say nothing groundbreaking happens. If you started at book 1 and enjoy spending time with Iris and Gwen, this book will fulfill that promise.

I thought that this was a solid addition to the Sparks & Bainbridge series, but not my favorite. I found it a bit darker, covering more sordid subject matters than some of the prior books. I think since the author switched to a different publisher, these books have become noticeably darker and more serious. Books 1-6 (published by Minotaur) were lighter cozy mysteries with witty banter and romantic elements. Books 7-8 (published by Severn House) feel more like thrillers or women's fiction. The fast-paced, sharp, witty dialogue is still there, but think West Wing, not Bridgerton. Which you prefer is a matter of personal taste, but I think it's a change that may lose some of the audience that got into the series from the beginning. Also, and this is speculative on my part, I think readers of WWII mysteries may be looking for a certain type of straightforward black and white/good vs evil escapism and the people and stories described in this book are all shades of gray, up until the end, which might make it hard to find an ideal audience, especially when it's book 8 of a series.

I found the blurb of this book misleading. Not only does it make the book sound more fun, like the earlier cozy mysteries, it also hints at a direct continuation of earlier plot lines. However, my impression was that this book mostly ignores earlier plot lines (e.g. no exploration of Gwen's roles as a working mother and competent business woman, or progress in her relationship with Sally; Iris is not clearly healing from her recent loss and no developments in the will they won't they relationship with Mike). On the plus side, I do think this book is a better "stand alone" story than the last 2 books, and a good entry point for readers looking for mysteries set in the post-WWII era.

The mysteries were satisfying and I was able to guess one of the reveals fairly early and another one of the reveals just beforehand based on the clues that the author left. One of the mysteries was left unsolved but it was still a satisfying and thoughtful way to end the story in my opinion. Romance was a missing element of this book, if that is something you are looking for, prepare for disappointment. It was a fairly short read, I finished it over 2 nights. I think the earlier books were generally in the 300 page range and books 7-8 under the new publisher have been in the 200 page range.

Thanks to Allison Montclair (aka Alan Gordon), Severn House, and Negalley for the ARC
1 review
January 8, 2026
The action continues in the eighth installment of the Sparks and Bainbridge series, this time with a blast from Sparks' past as they investigate an old friend from her college days. This was not my favorite of the series, as it felt a lot different from past books. Instead of explaining more about Gwen and her past and present as she fights for her son in court (since that plot line was tied up in the previous books), the eighth book focuses on Sparks and her backstory that has been hinted at throughout this series. Because of that, this book has a lot of darker themes and we see more of the reasoning behind her character and personality. I wanted to see more of her wrestling with losing Archie and the tightening of a couple loose plot holes that I saw more of in the past few books, such as her relationship with the rest of the gang now that Archie is dead, as well as with his family. I was left with a lot of questions at the end of book six and the beginning of book seven and most of them have still not been answered. Maybe the ninth book will start digging into more of those. I was also wanting to see more of Gwen in this book — she felt more of an accessory in this book, rather than an equal partner as in previous books. One of the things I enjoy about this series is how both Gwen and Sparks take turns discovering key facts about the case. In this book, that didn’t feel like such a central aspect of the development, instead focusing more on Sparks and her plans for solving the case. All that to say, I did really enjoy reading this book, despite the more disappointing aspects. The dynamic between Sparks and Gwen was still there, albeit navigating through the heavier tone and darker themes of this book. I loved that in seeing more of Sparks’ backstory we got to glimpse more of her character — which not only made Sparks a more interesting character, but also allowed this story to shine apart from the rest of the series, not merely following a formula, but giving us unique information. With the heavier content of this book, there are a couple content warnings I'd add (discussion of rape and suicide), but nothing was gratuitously dealt with or described in detail. I'd recommend this to older teens or adults looking for a thrilling post-WW2 mystery featuring ride-or-die friendship, disguises, intelligence agencies, a dash of romance, and the classic eleventh-hour villain reveal.

Thanks to NetGalley and Severn House for the ARC! All opinions are my own.
Profile Image for Robin.
588 reviews73 followers
November 29, 2025
I flat out love this series. The two main characters are wonderful, the time period – post war London, circa late 1940’s – is fascinating, and the plotting is spectacular. Montclair is simply writing one of the best traditional detective series right now. In this outing, our heroines, Iris Sparks and Gwen Bainbridge, are tasked by government intelligence to assign someone through their marriage bureau (The Right Sort) as a means to discover if a certain diplomatic employee is loyal to the government or working for another country. The woman they assign will be an agent.

The man, Tony Danforth, is an old classmate of Iris’ at Oxford. She has extremely mixed feelings about this assignment, but she owes a debt to the intelligence corps, and she and Gwen can’t get out of it. As she renews her friendship with Tony, who has been out of the country for quite awhile, her doubts increase, and they increase even more when she and Gwen meet the woman intended for Tony.

Iris doesn’t take to the brash young blonde agent but the meeting with Tony is set up and the first date goes well, only to end very badly. The investigation taken on by Iris and Gwen delves into Iris’ past and zeroes in on a terrible incident back in the 30’s during a house party. Iris and Tony were present but aren’t quite sure what happened, and tragically, the incident was followed by a suicide.

As Gwen and Iris search for a solution, Soviet involvement cannot be discounted, but neither can the incident from the past, and the two women follow family threads to try and find out just what happened. This is especially effective as the reader is unsure of anyone’s motives (except for Iris’ and Gwen’s) and unsure of which is the right thread that will solve the mystery. Montclair spools out her story brilliantly, capitalizing on Iris and Gwen’s smarts and innate bravery in the face of danger.

What makes it complex are the loyalties involved – to the government, to old friends – and what the truth of the matter is and how to discover it. The solution could not be more ingenious – it’s worthy of Ngaio Marsh – and I didn’t see it coming. Playing with the different tropes of the golden age, Montclair makes this outing all her own, further delineating the personalities of Iris and Gwen in the process. This is the work of a master.
Profile Image for Margie Bunting.
863 reviews41 followers
October 15, 2025
Fire Must Burn by Allison Montclair (aka Alan Gordon) is the eighth Sparks and Bainbridge Mystery--one of my favorite historical mystery series. Iris Sparks was an agent for British Intelligence in World War II, and Gwen Bainbridge lost her husband to the war and had to struggle to regain custody of their young son from her in-laws. When they met after the war, they decided to open The Right Sort Marriage Bureau together, and they have made a success of it. But at the same time, they have participated in some dangerous post-WWII projects for Iris's 's former boss.

Iris's friend at Cambridge University, whom she hasn't seen for years, is suspected of being a double agent for Russia, and Iris is instructed to sign up him for the Marriage Bureau's services, so that a female masquerading as a romantic prospect can be planted to obtain inside information. But after a violent attack occurs, street-smart Iris and elegant Gwen get more involved to determine who has motive to cause such mayhem before a further disaster occurs.

Montclair's writing style is, in my opinion, the star of these books--particularly the clever, sparkling dialogue. The characters of Iris and Gwen. who have become fast friends despite their very different personalities and sensibilities, are becoming ever stronger and more surprising as they learn from each other. The plots in this and all of the previous books are strong and fascinating, often with guilty parties that are quite unexpected. I heartily recommend this engrossing series.
Profile Image for TBS.
134 reviews
Review of advance copy received from Netgalley
January 5, 2026
In this 8th book of the Sparks & Bainbridge series, Montclair manages to deepen the characters even further (is this possible now that they are both being psychoanalyzed-yes!) and add a subplot twist that sadly echoes the contemporary MeToo movement. It begins when Sparks and Gwen are arm-twisted by the Brigadier into investigating Tony Danforth, a recently returned old college friend of Iris, who may be a Soviet or Chinese double agent. The honey trap is through their marriage agency, Tony is the target, and the Brigadier has a young Iris 2 waiting for her trial run at espionage. And then things get very complicated very quickly and Sparks must revisit and confront a tragic, uncomfortable and morally questionable event during her college years, which reaches into her present life. This book, introduces characters that seemed to have stepped out of a 40s Noir film, and this fit the subject matter so effectively, that at times, the line between reading a book and watching an imaginary movie got blurry. The rich and witty dialog is happily what we have come to expect from Montclair; the big reveal was a fork in a socket kind of shocker and yet, the bigger reveal for me was the courage and atonement demonstrated by the main characters. I wasn’t expecting that, and was impressed that it was accomplished in little over 250 pages. So now how long do I have to wait for book 9? My gratitude for NetGalley for access to this ARC.
Profile Image for Cindy Crawford.
138 reviews4 followers
Review of advance copy received from Netgalley
January 5, 2026
This series gets better and better. Gwen Bainbridge and Iris Sparks, on the surface, couldn't be more different. But they are good friend and successfully manage a marriage business in post WWII Britain--and they also help to solve crimes.

In the previous stories we've learned a lot about Bainbridge's past, and we've learned bits and pieces about Sparks' past, mainly that she worked for an intelligence agency during the war. In this book, we get to see a good deal more about Iris in the past. Some of the book is even written from her perspective as a 17-year old.

Consequences from past cases mean that Bainbridge and Sparks can't say no when Iris's previous boss, the Brigadier, recruits the marriage bureau to help in his agency's investigation into a possible double agent. But the suspected spy is an old friend of Sparks, and neither woman feels good about the deception they must play. They feel even worse when someone tries to murder the old friend. Soon they are totally engaged in an investigation that keeps uncovering secrets from the past--Iris's past.

The character development is great, and I loved the way the solution to the mystery in the book is slowly uncovered. There are some twists and turns, but they all ultimately make sense in the story. This is a great addition to the series.

I received a free ARC from NetGalley.
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287 reviews3 followers
November 10, 2025
I’ve really enjoyed the Sparks and Bainbridge Mysteries. They’re always clever, engaging, and keep my mind working to solve each case. This installment was a bit slower than the others for me. It picked up around the midway point, but lost momentum again before the ending. Overall, it didn’t feel quite as captivating as the previous books.
Sparks remains such an intriguing character, full of secrets and depth, but since Archie’s passing, her story arc feels a little stalled. I was hoping to see more growth from her in this one. Gwen continues to be her calm, steady self, and I’ve enjoyed her arc through the series.
While there are no open-door scenes, there are mentions of sexual assault, both in Sparks’ past and a scene where a rape attempt is stopped in the present. There is also a section that implies swinging (not with the main characters).
Though this mystery didn’t grip me as strongly as the others, I still enjoyed returning to this world. I’m hopeful the next book will bring more development for Sparks and also give her something happy to look forward to after all she has lost and endured. 3.5/5 stars.

Thank you to NetGalley and the publisher for providing a free copy of this book in exchange for my honest review.
Profile Image for Helen.
600 reviews16 followers
Review of advance copy received from Netgalley
January 4, 2026
I thank NetGalley and Severn House for an advance reader copy of Fire Must Burn. All opinions and comments are my own.

Will anything ever be easy for Iris Sparks and Gwen Bainbridge? They’re dropped right back into the spy business in Fire Must Burn, when Iris is told (not asked, not really) to help identify a possible Soviet spy. A man she knows very, very well from happier, pre-war times.

The elaborate ploy to discover the truth begins to take shape. Then… almost disaster. What follows from that is the action, situations and, especially, dialog that the series is known for. No wasted words or dawdling pages here; Iris and Gwen are up to their lovely necks in determining what is truly going on. All within the settings of a post-war Britain that is still trying to find its bearings, a world that author Allison Montclair illustrates so brilliantly.

The finalé sees compromises and judgements given over to the future, for good or for ill. Iris has had another chapter in her past exposed and questioned, and must examine her responses and her involvement once again. Readers are always kept thinking when they read a Sparks and Bainbridge story, and Fire Must Burn is no exception.
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766 reviews8 followers
January 16, 2026
5/5 stars: This Montclair's eighth entry in the Sparks & Bainbridge Mystery series which is a Historical Mystery set in 1947 England. Featuring a former intelligence agent and a widowed mother, who run a marriage bureau, as they turn sleuth to clear an old friend who's suspected of being a Soviet operative and an undercover agent. Spurred by the government to take him on as a client to help uncover his loyalties, the two women are shocked when he's nearly killed in an explosion. The pair are determined to sift through the man's past and present to uncover the truth behind this heinous crime.

With plenty of twists and turns, Montclair has masterfully crafted a mystery that deftly balances the suspects and weaves in plenty of clues and red herrings that will leave you pondering the whodunit until the final reveal. Witty and heartfelt, Montclair's writing and character work are stellar; the characters are well-rounded and complex while remaining incredibly likable with a secondary cast that are well crafted and uniquely voiced. The historical research Montclair's done is evident and well done without overshadowing the overall mystery plot and providing a sense of time and place perfectly.

With tact and sensitivity, Montclair takes on some sensitive issues; so take care and check the CWs. While you could read this as a stand-alone, you'll gain so much more by reading the series from the beginning; so be sure to pick up book one, The Right Sort of Man.

I received this eARC thanks to NetGalley and Severn House in exchange for an honest review. Publishing dates are subject to change.
228 reviews6 followers
February 16, 2026
Fire Must Burn is the eighth installment of Allison Montclair’s Sparks and Bainbridge mystery series set in post-World War II London, in which feisty, fierce, fascinating, and foxy Iris and Gwen run a marriage bureau and find themselves dealing with murder and mayhem on the side. And somehow the series just keeps getting better and better,

I loved reading this immersive and entertaining tale. By turns humorous and heart wrenching, complex yet propulsive, the novel is very well crafted, with crisp and witty dialogue. The characters of Iris and Gwen are beautifully developed, with each woman portrayed as having smarts and gumption but also plenty of relatable flaws and fears. The large cast of secondary characters is vividly drawn. The extent of Montclair’s research is additionally apparent, as she once again manages to utterly transport the reader to postwar London, with just enough period specific details sprinkled throughout. I look forward to discovering Iris and Gwen’s future shenanigans and life choices in the next installment of this series.

Highly recommended, particularly to anyone seeking intelligent historical mysteries featuring strong, interesting women.

Many thanks to NetGalley and Severn House for a complimentary ARC. Opinions are my own.
253 reviews2 followers
October 7, 2025
Fire Must Burn is the latest Sparks and Bainbridge mystery set in England just after WWII. I love this series and I was so excited to get to read this newest mystery. It did not disappoint! The mystery was so full of twists and turns and I was shocked to find out who the murderer was. I did not see that coming! I liked how much this book focused on Gwen and Iris working together - two emotionally damaged women that are becoming healthier and stronger and really good at what they do, even if there is much more going on than a little matchmaking. These two women have really come into their own and it has been so interesting to see the characters grow and develop over the course of the series. I also liked how even though the mystery got wrapped up at the end, it was a very gray ending. I don’t know how else to describe it, but sometimes things are not cut and dried and they certainly aren’t in this series. This was definitely one of my favorite books in this series. The research and writing are impeccable and I am already waiting for the next book in the series!

Thank you to NetGalley and the publisher for the chance to read this book. All opinions are my own.
Profile Image for hannah ⊹ ࣪ ˖.
450 reviews9 followers
November 11, 2025
I always love returning to Iris and Gwen, and Fire Must Burn might be one of my favorite installments so far. Montclair continues to blend wit, charm, and just the right amount of tension in postwar London. The stakes feel higher this time — with Iris drawn back into the shadowy world of espionage and Gwen balancing the everyday pressures of their matchmaking business — but it never loses the warmth and humor that make this series shine.

The dialogue sparkles, the historical detail feels effortless, and the friendship between the two women remains the true heart of the story. Their banter and loyalty are what keep me turning pages even more than the mystery itself. The spy plot is engaging and twisty enough to stay interesting, though a couple of reveals were easy to spot coming. Still, it’s a clever, confident mystery that feels both classic and fresh.

If you like your historical fiction with sharp women, dry humor, and a dash of danger, this is a must-read. Montclair has such a knack for balancing coziness with intrigue — Fire Must Burn is exactly that: comforting, clever, and quietly fierce.

Thank you so much to NetGalley and Severn House for the eARC!
11.5k reviews197 followers
Review of advance copy received from Netgalley
December 31, 2025
Gwen and Iris are back! This latest in the series (probably most appreciated by those familiar with it) sees Iris being confronted with her past. It's 1947 and the Brigadier has enlisted the Marriage Bureau (aka Gwen and Iris) to help determine whether her old pal Anthony Danforth is working for the Russians. Iris can't imagine it but they agree to put one of the Brigadier's assets in his path for a date. And then Tony's new flat is firebombed. Iris can't let go-she knows there's more afoot than meets the eye and believes it relates to something that happened when they are at Cambridge. This moves back and forth in time to expand on that. This has great period atmospherics, terrific characters, and an issue that continues to be , well, no spoilers. We don't spend much time with Gwen but that's ok because she's been the focus in earlier installments. Iris on the other hand becomes more fleshed out, especially with regard to secrets she's kept. Thanks to Netgalley for the ARC. I'm a fan of the series, thoroughly enjoyed this installment and eagerly await the next one. Great read.
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