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The Undetectables #3
The Unfathomable Curse
A witty, witchy fantasy murder mystery packed with ancient magic and fiendish puzzles. When Cornelia’s twin sisters are taken by the Wickermere Reaper, Mallory, Diana and Theodore must race against time to uncover the buried secrets of the Broadwicks before it’s too late. Perfect for fans of supernatural mysteries and cosy crime by authors such as Ben Aaranovitch, Josiah Bancroft and Tammie Painter.
The summer after the events of The Undead Complex, the unthinkable finally happens – Cornelia’s money is running out. Estranged from her family, furious at her parents following recent revelations, the Broadwick heir finds herself living on her own resources for the first time.
Meanwhile two crimes are rocking the Apparent community. The Wrackton Digger is stealing bodies from the cemetery, and a new serial killer – the Wickermere Reaper – has emerged. But when the Reaper snatches their next victims – Cornelia’s twin sisters – she must return to her family’s home, and seat of the Ghoul Council, to conduct the search.
With their resources split, and a ticking clock on the race to save the twins, The Undetectables must do what they do best – solve the strangest, most well-hidden magical mysteries to save the people they love.
The summer after the events of The Undead Complex, the unthinkable finally happens – Cornelia’s money is running out. Estranged from her family, furious at her parents following recent revelations, the Broadwick heir finds herself living on her own resources for the first time.
Meanwhile two crimes are rocking the Apparent community. The Wrackton Digger is stealing bodies from the cemetery, and a new serial killer – the Wickermere Reaper – has emerged. But when the Reaper snatches their next victims – Cornelia’s twin sisters – she must return to her family’s home, and seat of the Ghoul Council, to conduct the search.
With their resources split, and a ticking clock on the race to save the twins, The Undetectables must do what they do best – solve the strangest, most well-hidden magical mysteries to save the people they love.
496 pages, Paperback
First published September 23, 2025
200 people want to read
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Displaying 1 - 15 of 15 reviews
August 20, 2025
“Queer witchcraft perfection”
Thank you to Net Galley and the publishers for sending me a copy in exchange for a review.
This series has my heart. So I'm a little biased.
The inclusivity, the disability rep, the queerness - perfection.
I love the group dynamics between our besties Cornelia, Mallory and Diana especially with the slow burn will they won't they between Mallory and Cornelia. Theodore is worrying me and I can't wait to get my mitts on the next book because I need my cat eared friend to be okay.
The plot had me on the edge of my seat, and although the investigation did lose me at some points (that's more of a my brain isn't braining rather than the book being badly written) this is definitely upping the stakes that were introduced in book one.
Perfect read for cosy autumn evenings and anyone who likes a little witchcraft in their reads.
Thank you to Net Galley and the publishers for sending me a copy in exchange for a review.
This series has my heart. So I'm a little biased.
The inclusivity, the disability rep, the queerness - perfection.
I love the group dynamics between our besties Cornelia, Mallory and Diana especially with the slow burn will they won't they between Mallory and Cornelia. Theodore is worrying me and I can't wait to get my mitts on the next book because I need my cat eared friend to be okay.
The plot had me on the edge of my seat, and although the investigation did lose me at some points (that's more of a my brain isn't braining rather than the book being badly written) this is definitely upping the stakes that were introduced in book one.
Perfect read for cosy autumn evenings and anyone who likes a little witchcraft in their reads.
September 19, 2025
4.5 stars
If you've been following me for a while, you'll know how much I loved this series and these characters. I love Courtney Smyth's writing and have fallen in love with this world, which continues to develop as the series goes on.
One of the things I love the most about this series is its characters and the representation throughout, from LGBTQ+ to invisible disabilities such as fibromyalgia, hearing loss, and agoraphobia. The latter is one I can relate to very personally as I suffer from it, and it was so nice to see it represented as agoraphobia is not one many people write about.
I really loved getting to see more of Cornelia in this one and learning more about their family dynamics, or lack of. They are such a strong character who has already gone through so much only to find themselves on the case of their missing twin sisters. They grow so much as a character in this book, and I honestly felt like a proud best friend to all three of our main characters throughout.
This was honestly such a mysterious and tense read that had me on tender hooks, needing to know what happened next with both of the cases The Undetectables found themselves on. I did not see those twists and turns coming, and I can't recommend this series enough. I am so excited for the next book!
If you've been following me for a while, you'll know how much I loved this series and these characters. I love Courtney Smyth's writing and have fallen in love with this world, which continues to develop as the series goes on.
One of the things I love the most about this series is its characters and the representation throughout, from LGBTQ+ to invisible disabilities such as fibromyalgia, hearing loss, and agoraphobia. The latter is one I can relate to very personally as I suffer from it, and it was so nice to see it represented as agoraphobia is not one many people write about.
I really loved getting to see more of Cornelia in this one and learning more about their family dynamics, or lack of. They are such a strong character who has already gone through so much only to find themselves on the case of their missing twin sisters. They grow so much as a character in this book, and I honestly felt like a proud best friend to all three of our main characters throughout.
This was honestly such a mysterious and tense read that had me on tender hooks, needing to know what happened next with both of the cases The Undetectables found themselves on. I did not see those twists and turns coming, and I can't recommend this series enough. I am so excited for the next book!
September 25, 2025
The Unfathomable Curse is the third book in Courtney Smyth's ongoing The Undetectables series and I was so happy to be reunited with this group of characters who are some of my favourites in fiction. As it is the third book I don't think it is a great place to pick up the series, you really do need to have read the first two books to get the most out of this one, there is no real attempt to help new new readers to catch up, but since the series is so good over all I have no qualms in recommending that you pick those up as soon as you can!
This book has two parallel mysteries, though the focus is really on the Wickermere Reaper, a serial killer who has kidnapped the twin sisters of Cordelia, one of the Undetectables. Despite being estranged from her family Cordelia is determined to bring the skills of the Undetectables to the table and help to find them before time runs out, a gesture that is not entirely welcomed by Cordelia's family or the Ghoul Council who are nominally in charge of the investigation. The second mystery involves the Wracton Digger, someone who is not killing, but instead is disturbing graves and stealing bodies. To be honest this plotline irritated me through most of the book as it seemed irrelevant and felt a little like padding but I should have know to trust the author, the ending of the book ties both plotlines together in a way that is both satisfying and had me desperate to find out where the story is going next.
For me the heart and soul of this book is the wonderful group of characters and the powerful friendships and relationships they share. I really appreciate how kind they are to each other and accepting of one another and understanding of their various needs. The representation in this book, and the series as a whole ,both in terms of LGBTQIA+ characters and disability representation is top notch, and I love how well the author incorporates it into the storytelling and how the character's journeys continue to evolve as the series continues.
I read and reviewed an ARC courtesy of NetGalley and the publisher, all opinions are my own.
This book has two parallel mysteries, though the focus is really on the Wickermere Reaper, a serial killer who has kidnapped the twin sisters of Cordelia, one of the Undetectables. Despite being estranged from her family Cordelia is determined to bring the skills of the Undetectables to the table and help to find them before time runs out, a gesture that is not entirely welcomed by Cordelia's family or the Ghoul Council who are nominally in charge of the investigation. The second mystery involves the Wracton Digger, someone who is not killing, but instead is disturbing graves and stealing bodies. To be honest this plotline irritated me through most of the book as it seemed irrelevant and felt a little like padding but I should have know to trust the author, the ending of the book ties both plotlines together in a way that is both satisfying and had me desperate to find out where the story is going next.
For me the heart and soul of this book is the wonderful group of characters and the powerful friendships and relationships they share. I really appreciate how kind they are to each other and accepting of one another and understanding of their various needs. The representation in this book, and the series as a whole ,both in terms of LGBTQIA+ characters and disability representation is top notch, and I love how well the author incorporates it into the storytelling and how the character's journeys continue to evolve as the series continues.
I read and reviewed an ARC courtesy of NetGalley and the publisher, all opinions are my own.
October 4, 2025
Originally posted on my blog Nonstop Reader.
The Unfathomable Curse is the third mystery featuring an ensemble cast of misfit paranormal detectives by Courtney Smyth. Released 23rd Sept 2025 by Titan Books, it's 496 pages and is available in paperback and ebook formats. It's worth noting that the ebook format has a handy interactive table of contents as well as interactive links throughout.
This is a queer friendly paranormal investigative team with multiple representations including disabled, witchy, and breathing-challenged (i.e., a ghost). There's a bit of a scooby-doo vibe along with a very well fleshed-out magical system and interesting three dimensional characters.
Although the denouement and resolution are self-contained in this book, the plot follows on *heavily* from the backstory and setup in the earlier books, so readers who come into the series with this book will likely be somewhat lost for a while. It's an ongoing series, but each installment is self contained with a complete (and satisfying) story arc.
Four stars. Serviceable plot, well written characters, plotting maybe a trifle slow (it's a hefty book), but overall recommended for fans of UF/fantasy/mystery/paranormal. Language and graphic content are roughly R-rated. It would be a good choice for public library acquisition, or for a marathon binge/buddy read (roughly 1500 pages extant so far).
Disclosure: I received an ARC at no cost from the author/publisher for review purposes.
The Unfathomable Curse is the third mystery featuring an ensemble cast of misfit paranormal detectives by Courtney Smyth. Released 23rd Sept 2025 by Titan Books, it's 496 pages and is available in paperback and ebook formats. It's worth noting that the ebook format has a handy interactive table of contents as well as interactive links throughout.
This is a queer friendly paranormal investigative team with multiple representations including disabled, witchy, and breathing-challenged (i.e., a ghost). There's a bit of a scooby-doo vibe along with a very well fleshed-out magical system and interesting three dimensional characters.
Although the denouement and resolution are self-contained in this book, the plot follows on *heavily* from the backstory and setup in the earlier books, so readers who come into the series with this book will likely be somewhat lost for a while. It's an ongoing series, but each installment is self contained with a complete (and satisfying) story arc.
Four stars. Serviceable plot, well written characters, plotting maybe a trifle slow (it's a hefty book), but overall recommended for fans of UF/fantasy/mystery/paranormal. Language and graphic content are roughly R-rated. It would be a good choice for public library acquisition, or for a marathon binge/buddy read (roughly 1500 pages extant so far).
Disclosure: I received an ARC at no cost from the author/publisher for review purposes.
October 17, 2025
Cornelia's money is finally running out now that she's estranged from her family after the events of the Undead Complex. The Wrackton Digger is stealing bodies from the cemetery, and the Wickermere Reaper has emerged as a new serial killer. When the Reaper snatches Cornelia’s twin sisters as their next victims, she must return to her family’s home, and seat of the Ghoul Council, to conduct the search. The Undetectables have a ticking clock to save the twins, and still must find the Wrackton Digger. They are determined to do it and save the people they love.
This is the third book in the Undetectables series, and you absolutely have to read the first two novels first. We backtrack a bit at first, so we see how Cornelia grew up, and it really explains a lot. The current-day investigation proceeds slowly as the entire team is pulled into the body snatching case, then into the missing twins. The missing person case has a short timeline and an intense emotional cost for Cornelia, and we see the Council adhering to policy and procedures at all costs, sometimes actively blocking the Undetectables from getting any accurate information to find the twins. More bodies go missing, splitting the attention of allies and upping the tension as the book progresses.
The final third of the book has a lot of information and betrayals, reversals, and the curse being laid. It allows a ghost to take over a living body completely, and the former soul is lost forever. The curse is one that witches fear and is impossible to get out of. The two cases are solved by the end, though we only have the motive for one of them. There will undoubtedly be another book in this series, because there are unanswered questions and a new ticking clock for the team to deal with.
This is the third book in the Undetectables series, and you absolutely have to read the first two novels first. We backtrack a bit at first, so we see how Cornelia grew up, and it really explains a lot. The current-day investigation proceeds slowly as the entire team is pulled into the body snatching case, then into the missing twins. The missing person case has a short timeline and an intense emotional cost for Cornelia, and we see the Council adhering to policy and procedures at all costs, sometimes actively blocking the Undetectables from getting any accurate information to find the twins. More bodies go missing, splitting the attention of allies and upping the tension as the book progresses.
The final third of the book has a lot of information and betrayals, reversals, and the curse being laid. It allows a ghost to take over a living body completely, and the former soul is lost forever. The curse is one that witches fear and is impossible to get out of. The two cases are solved by the end, though we only have the motive for one of them. There will undoubtedly be another book in this series, because there are unanswered questions and a new ticking clock for the team to deal with.
August 16, 2025
The unfathomable curse by Courtney Smyth review
Genre: fantasy/mystery
Rep: LGBTQ+, POC, Disability (MC’s with fibromyalgia, hearing loss + hearing aids, PTSD, agoraphobia, undiagnosed ADHD. SC’s with ostomy bag, Deaf with sign language).
Thank you for NetGalley and Titan books for this ARC in exchange for an honest review.
The unfathomable curse is the 3rd book in de Undetectables series, with the first book being Mallory’s book, the second book Diana’s and this book focusing on Cornelia. With a time sensitive murder mystery on their hands, Cornelia has to stay sharp while confronting her family.
As always, this book is full of amazing minority representation with our main characters being Queer, racially diverse and disabled. I love how each book gives us insight into the lives and obstacles each member of the Undetectables face. Finally getting to know Cornelia on such a deep level was a journey I wish I could experience twice. As with the last book, the Undetectables are called to investigate while one of them is very close to the people involved in the mystery. This makes perfect room to get to know Cornelia’s dynamic with her family. This is also the first time we actually get to know the family members.
The main things I loved about Diana’s book were repeated in a different flavour in this one, like the two investigations side by side with a difference between the main investigation and the side investigation. Still, the side investigation proved very important at the end, especially to speculate on the sequel. However, I think this book’s pacing would’ve been more than fine without the side investigation, although it added much more mystery and suspense overall. I truly can’t complain about it’s addition to the plot.
If I absolutely have to be critical it is that the beginning of the book takes us into the investigation that differs from the blurb on the book, so it left me a bit confused after a while as it takes a bit for the main plot to reveal itself. However, in my opinion the rest of the book is perfect. I didn’t know I could relate to Cornelia so much, especially with the PTSD rep and agoraphobia. After reading this book, Cornelia is so much more than the Rich Bitch (affectionately) of the three witches.
Please go read this series!
Genre: fantasy/mystery
Rep: LGBTQ+, POC, Disability (MC’s with fibromyalgia, hearing loss + hearing aids, PTSD, agoraphobia, undiagnosed ADHD. SC’s with ostomy bag, Deaf with sign language).
Thank you for NetGalley and Titan books for this ARC in exchange for an honest review.
The unfathomable curse is the 3rd book in de Undetectables series, with the first book being Mallory’s book, the second book Diana’s and this book focusing on Cornelia. With a time sensitive murder mystery on their hands, Cornelia has to stay sharp while confronting her family.
As always, this book is full of amazing minority representation with our main characters being Queer, racially diverse and disabled. I love how each book gives us insight into the lives and obstacles each member of the Undetectables face. Finally getting to know Cornelia on such a deep level was a journey I wish I could experience twice. As with the last book, the Undetectables are called to investigate while one of them is very close to the people involved in the mystery. This makes perfect room to get to know Cornelia’s dynamic with her family. This is also the first time we actually get to know the family members.
The main things I loved about Diana’s book were repeated in a different flavour in this one, like the two investigations side by side with a difference between the main investigation and the side investigation. Still, the side investigation proved very important at the end, especially to speculate on the sequel. However, I think this book’s pacing would’ve been more than fine without the side investigation, although it added much more mystery and suspense overall. I truly can’t complain about it’s addition to the plot.
If I absolutely have to be critical it is that the beginning of the book takes us into the investigation that differs from the blurb on the book, so it left me a bit confused after a while as it takes a bit for the main plot to reveal itself. However, in my opinion the rest of the book is perfect. I didn’t know I could relate to Cornelia so much, especially with the PTSD rep and agoraphobia. After reading this book, Cornelia is so much more than the Rich Bitch (affectionately) of the three witches.
Please go read this series!
September 23, 2025
Thank you NetGalley and Titan books for an ARC copy of this book! *all thoughts and opinions are my own*
I really enjoyed this book! It is the 3rd in a series but I haven’t read the first 2 (I think I will go back and read them) but I understood what was happening and it didn’t feel like coming in on a 3rd book!
I loved the main 3 characters and how they were all different! I also loved the different representation in the book (and the authors note at the end made it more special). I feel that representation in books is very important in this day and age with what is going on in the UK and around the world.
I enjoyed having ghosts, vampires, faeries, demons and many other magical beings in an urban fantasy setting.
The mystery kept me guessing the whole way through and the twists did get me I did not guess the ending at any point!
Overall I really enjoyed this book and would recommend it if people are looking for a fantastical mystery novel!
I really enjoyed this book! It is the 3rd in a series but I haven’t read the first 2 (I think I will go back and read them) but I understood what was happening and it didn’t feel like coming in on a 3rd book!
I loved the main 3 characters and how they were all different! I also loved the different representation in the book (and the authors note at the end made it more special). I feel that representation in books is very important in this day and age with what is going on in the UK and around the world.
I enjoyed having ghosts, vampires, faeries, demons and many other magical beings in an urban fantasy setting.
The mystery kept me guessing the whole way through and the twists did get me I did not guess the ending at any point!
Overall I really enjoyed this book and would recommend it if people are looking for a fantastical mystery novel!
September 5, 2025
Every time I finish a book in this series its like TAKE THIS CLIFFHANGER and then I suffer until the next one comes out.
I love puzzling along with the clues to figure out the mystery its so much fun even when I'm not smart enough to get it right 😂
And the queer rep??? The chronic pain rep?? I love it so much. Cornelias whole journey in this book was felt in my heart because it feels similar to how I often think about gender and stuff
Anyways I'll be yelling into the abyss for a while now about the fact that I don't know when book 4 will come out.
Thanks so much to netgalley for sending me an ARC for this book!
I love puzzling along with the clues to figure out the mystery its so much fun even when I'm not smart enough to get it right 😂
And the queer rep??? The chronic pain rep?? I love it so much. Cornelias whole journey in this book was felt in my heart because it feels similar to how I often think about gender and stuff
Anyways I'll be yelling into the abyss for a while now about the fact that I don't know when book 4 will come out.
Thanks so much to netgalley for sending me an ARC for this book!
September 29, 2025
Rounded up from 3.5 Stars.
Another good book in the series! This series is one I really enjoy. It has such wonderful cast of queer characters, and I love the dynamic between all of the friends. I think there is at least one thing in each character that someone can connect to. It feels really good to read something and see all kinds of representation.
Since book 1, I've really enjoyed the concept of the magical forensics and entomology, and that just continues throughout. A witch run PI agency? Sapphic yearning? Found family? Sign me up. There's so much about this series to enjoy.
Another good book in the series! This series is one I really enjoy. It has such wonderful cast of queer characters, and I love the dynamic between all of the friends. I think there is at least one thing in each character that someone can connect to. It feels really good to read something and see all kinds of representation.
Since book 1, I've really enjoyed the concept of the magical forensics and entomology, and that just continues throughout. A witch run PI agency? Sapphic yearning? Found family? Sign me up. There's so much about this series to enjoy.
July 31, 2025
The Unfathomable Curse is an enchanting mix of mystery, dark magic, and sharp wit that completely pulled me in. Beyond the clever puzzles and eerie suspense, what truly struck me was the emotional depth, Cornelia’s strained family ties and her desperate fight for her sisters give the story a heart that lingers long after the last page. A perfect blend of intrigue, atmosphere, and humanity, it’s both thrilling and unexpectedly moving.
August 13, 2025
A deliciously dark tangle of magic, murder, and mystery, The Unfathomable Curse delivers both chills and charm. Smyth weaves a sharp-witted, atmospheric tale where family drama and supernatural danger collide, and Cornelia’s hunt for her kidnapped sisters brims with tension and heart. Beautifully written, richly imagined, and satisfyingly twisty—this cosy-meets-creepy fantasy mystery is one I couldn’t put down.
September 3, 2025
Sometimes a new to me series can sometimes hard to get into. In this case, it was definitely hard for me. I just couldn’t get into it and click with the story.
While I love the concept and I love the characters on the set up. I just really struggled to get through the book. I’m hoping the previous two entries may help nd I can move forward with the series.
While I love the concept and I love the characters on the set up. I just really struggled to get through the book. I’m hoping the previous two entries may help nd I can move forward with the series.
October 1, 2025
Every book in this series gets better. The plots are excellent and complicated with edge of your seat narration (and yes i skipped ahead a few times because i was so nervous about the outcome).
the undetectables are one of my favorite fictional friend groups and i cannot wait for the next book in the series.
the undetectables are one of my favorite fictional friend groups and i cannot wait for the next book in the series.
September 1, 2025
After spending the best part of a year avoiding her parents, Cornelia has been cut off from the Broadwick fortune, but still she can't bring herself to speak to them. And then the Wickermere Reaper abducts Cornelia's twin sisters, and she finds herself back in the family home, in a race against the clock to save their lives...
The Unfathomable Curse is the third book in The Undetectables series, and I don't know how well it would work as a standalone. In addition to the main plot revolving around the Wickermere Reaper, there is also a subplot focusing on the Wrackton Digger, a character arc for Cornelia, and an overarching storyline that spans the entire series. The main plot resembles those from the first two books, as Mallory, Diana, and Cornelia have to put their own lives on the line to solve a fiendishly complex magical mystery in a race against the clock. But instead of Wrackton, the setting is an evocatively eerie Wickermere, and instead of the friends they usually rely on to help them, the witches have only the Ghoul Council headed by Cornelia's parents, who are also their only suspects. I love a mystery centred around a small group of suspicious characters, and this one kept me guessing right until the end.
In the subplot, Theodore takes the lead on investigating the Wrackton Digger who is stealing bodies from the cemetery, but as the book draws to a close, it becomes increasingly clear that not only these two cases but all the Undetectables' cases are somehow connected. There is a lot going on in The Unfathomable Curse and it all ends on something of a cliffhanger. After The Undetectables focused on Mallory and The Undead Complex on Diana, in The Unfathomable Curse it is Cornelia's turn. As well as the main plot being centred around her family, we also get to see her processing the trauma of being abducted by the Whistler and dealing with her feelings about Mallory, the Broadwicks, and herself. I love that the series is structured like this, and I hope it is Theodore's turn next!
The Unfathomable Curse is out on 23 September. Thank you to NetGalley and Titan Books for an advance copy.
The Unfathomable Curse is the third book in The Undetectables series, and I don't know how well it would work as a standalone. In addition to the main plot revolving around the Wickermere Reaper, there is also a subplot focusing on the Wrackton Digger, a character arc for Cornelia, and an overarching storyline that spans the entire series. The main plot resembles those from the first two books, as Mallory, Diana, and Cornelia have to put their own lives on the line to solve a fiendishly complex magical mystery in a race against the clock. But instead of Wrackton, the setting is an evocatively eerie Wickermere, and instead of the friends they usually rely on to help them, the witches have only the Ghoul Council headed by Cornelia's parents, who are also their only suspects. I love a mystery centred around a small group of suspicious characters, and this one kept me guessing right until the end.
In the subplot, Theodore takes the lead on investigating the Wrackton Digger who is stealing bodies from the cemetery, but as the book draws to a close, it becomes increasingly clear that not only these two cases but all the Undetectables' cases are somehow connected. There is a lot going on in The Unfathomable Curse and it all ends on something of a cliffhanger. After The Undetectables focused on Mallory and The Undead Complex on Diana, in The Unfathomable Curse it is Cornelia's turn. As well as the main plot being centred around her family, we also get to see her processing the trauma of being abducted by the Whistler and dealing with her feelings about Mallory, the Broadwicks, and herself. I love that the series is structured like this, and I hope it is Theodore's turn next!
The Unfathomable Curse is out on 23 September. Thank you to NetGalley and Titan Books for an advance copy.
September 27, 2025
This was the first book I’ve read by the author. I loved the cover and title.
The book features characters from different backgrounds and it is a fantasy murder mystery. The author’s writing is very fluent, and the style is incredibly beautiful. If you enjoy mystery; then this book is for you!
This is an ARC review. I appreciate receiving this copy from NetGalley and the publisher in return for an honest review.
The book features characters from different backgrounds and it is a fantasy murder mystery. The author’s writing is very fluent, and the style is incredibly beautiful. If you enjoy mystery; then this book is for you!
This is an ARC review. I appreciate receiving this copy from NetGalley and the publisher in return for an honest review.
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