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The Balloonmakers #2

The Spy with the Red Balloon

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Siblings Ilse and Wolf hide a deep secret in their blood: with it, they can work magic. And the government just found out.Blackmailed into service during World War II, Ilse lends her magic to America’s newest weapon, the atom bomb, while Wolf goes behind enemy lines to sabotage Germany’s nuclear program. It’s a dangerous mission, but if Hitler were to create the bomb first, the results would be catastrophic.

When Wolf’s plane is shot down, his entire mission is thrown into jeopardy. Wolf needs Ilse’s help to develop the magic that will keep him alive, but with a spy afoot in Ilse’s laboratory, the letters she sends to Wolf begin to look treasonous. Can Ilse prove her loyalty—and find a way to help her brother—before their time runs out?

362 pages, Hardcover

First published October 2, 2018

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About the author

Katherine Locke

15 books510 followers
Katherine Locke lives and writes in a small town outside Philadelphia, where she’s ruled by her feline overlords and her addiction to chai lattes. She writes about that which she cannot do: ballet, magic, and time travel. She secretly believes all stories are fairytales in disguise. Her YA debut, THE GIRL WITH THE RED BALLOON, arrives September 2017 from Albert Whitman & Comapny.

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Displaying 1 - 30 of 129 reviews
Profile Image for Amy Leigh.
328 reviews38 followers
May 7, 2018
I really enjoyed this book just as much as the first in this series! They read in a way that if you read them out of order you would be okay but I don't recommend missing either book. The way the author intertwines magic and history into a ya fantasy novel is brilliant.

Ilse and Wolf are siblings with a special type of magic that comes from their blood. This is World War II and they are both tricked into using their magic for the war. Wolf is a spy working on the Germans to try to keep Nazi Germany from being able to succeed with nuclear weaponry. Ilse is actually working with Americans to help further the Atom bomb along. Ilse cant bear not knowing if her brother is okay and sends him letters that he holds dear. Wolf has a flying incident and Ilse's letters are found. She has to prove she isn't a traitor in a time period of great war and distrust.

​Thank you to Edelweiss and Albert Whitman & Company for an ARC in exchange for a fair and honest review.
Profile Image for Katherine Locke.
Author 15 books510 followers
September 24, 2017
UPDATE: 9/24/17
IT HAS A TITLE! The Spy with the Red Balloon will arrive Fall 2018 (if everything stays on track...). Please enjoy my Queer Jewish Kids Punch Nazis While Doing Science and Sabotaging Hitler book.

Previous review:
To be fair, I haven't finished writing this book yet. But I wanted to leave a review in case people had questions when The Girl with the Red Balloon #1 ARCs started to appear in the new year:

1. This is not a sequel. It takes place about 45 years BEFORE the first book and has only one overlapping secondary character. Same world, different characters.
2. This is literally all I can tell you. Not because of publishing secrets but because the book isn't written yet. When I can tell you more, I will!
Profile Image for Abi (The Knights Who Say Book).
633 reviews95 followers
August 4, 2018
My feelings about this book are intense and therefore completely indescribable, so this is going to be an utterly useless review.

Like, it has flaws? I definitely thought at times that the writing could just be overall better, and that it was too slow, and that it was somehow just not giving me enough even though I loved every concept in it. You know when you like a book but are at the same time completely exasperated by it? I think this book needed to give us more about Ilse's friends and how their relationships grow and deepen, and on Wolf's side needed to make us understand Lily more, because to be honest I felt like she was kinda flat, despite her importance, so overall her character is just weirdly handled.

But those problems weren't always problems. When there were fewer characters on screen, the relationship between Wolf and Ilsa really shone. I really liked the romance between Wolf and Max. And I've always liked Katherine Locke's version of magic as a science, even though it's kinda vague because, you know, she can't actually give us the magical equations Ilsa writes. Obviously, that would out magic to the whole world, and we can't have that.

And most importantly? Most fricken importantly? QUEER JEWS PUNCHING NAZIS.

I LOVE Wolf and Ilsa unapologetically going into the war exactly because they know their country isn't in it to save the Jews, but screw it, they are. They're Jewish and that grounds them. It's what puts them in danger, but it's also what inspires them. And they both discover in the process that they're definitely not straight, and even though that's also dangerous for them in this era, well, Katherine Locke is not here to let the nazis win.

Science. Spies. Magic. Kissing. It's a good book, guys.
Profile Image for Dahlia.
Author 18 books2,497 followers
September 23, 2018
I just can't get over how quickly and deeply I fell for these characters. As in the first book, some of the science and magic stuff went over my head, but I really didn't care. The writing is just so gorgeous, the characters so special, and the stakes so high I read this in a state of panic that was partly deserved but so well worth it.
Profile Image for Other Rachel.
154 reviews47 followers
August 15, 2018
"Get in, losers," she called out. "We're blowing up Nazis."


In a companion story to The Girl with the Red Balloon, the stakes are high as America joins the second World War. The government is tracking people with magic abilities, drafting them for the fight. Ilse and Wolf Klein are caught in the middle of practicing and are separated to do their necessary part in ensuring America’s survival. Combative Ilse is sent to lead a group in the Manhattan Project where a spy threatens to spill their secrets. Wolf is trained to be a spy where he unexpectedly collides with an old friend. Both work to understand the properties of their strange blood and what uses they could have beyond killing, and Ilse and Wolf are aware of what being Jewish means in the war effort.

I can describe this book in two words: Jewish catharsis. Coming from a similar background as the author and the siblings, it felt really good to see Nazis being punched by angry Jewish people. The fact that Ilse, Wolf, and the others aren’t used as tragedy porn because Locke understands the weight representation has. Privilege is explored through race, religion, sexuality, and gender, showing how these characters act in these intersections at the battleground and in the lab

This is an excellent read that has made me loudly cheer at each heroic fight, the relatable Jewish-ness, and how she perfectly worked in a Mean Girls reference.

I highly recommend reading this and be sure to have a copy of The Girl with the Red Balloon to enjoy the moment even more.

I've received the arc from Edelweiss in exchange for an honest review. All opinions are my own.
Profile Image for Kate Welsh.
Author 1 book94 followers
October 2, 2018
Spies! World War II! Math and science and magic all intertwined! Big difficult philosophical questions! Historical fiction including characters of diverse races and religions and sexualities! Complicated sibling and friendship and romantic dynamics! SO MANY THINGS I LOVE ALL TOGETHER.

UPDATED 10/2: Read my blog post about the book and interview with author Katherine Locke right here!
Profile Image for Julie .
874 reviews273 followers
August 16, 2018
This was a bit of a slow start for me, but I loved Wolfe and Ilse from page 1. As it went on, it became more and more addicting and I was desperate to get to each chapter and make sure everyone was okay. Also this was SO queer, which was wonderful.
Profile Image for Lia.
340 reviews94 followers
Shelved as 'dnf'
April 22, 2019
eh I'm not feeling it. I doubt I'll pick this one up again, so it's on the dnf shelf for now.
Profile Image for MsArdychan.
529 reviews22 followers
September 9, 2018
Please Note: I received an advance copy of this book from Edelweiss in exchange for an honest review. This did not influence the opinions of my review in any way.

Reading The Girl With The Red Balloon last year, I was struck by how the author, Katherine Locke created both an historical novel, and an imaginative fantasy novel. Her newest book, The Spy With The Red Balloon, takes place in the same universe of magic, but with a different historical setting and characters. Once again, I am blown away by the intricate plot, suspense, and historical details. Once I started reading, I could not put it down!

What I Liked:

Setting/Historical Details:
The book takes place during the second world war. The race is on to see who will create the first atomic bomb: The Americans, or Hitler. I loved all the details of that time that the author includes. From food shortages, and horrible beer to the institutional sexism and racism of the era, I felt these characters were definitely of that time.

The book centers on Jewish siblings, Ilse and Wolf. They both have magical blood which enables them to perform enchantments. But younger sister Ilse has the added talent of being a intellectual genius. At sixteen, she is already a university student when the military calls on her (forces her) to use her magical abilities in the war effort of WWII. Wolf, being a few years older, is also pushed into magical service.

I really liked Ilse. She is so young and immature to be thrown in with adults much older than she. Not only is she trying to solve an almost impossible puzzle, wrestling with the ethical implications of war, but she is also trying to navigate her attraction for another girl. Being the 1940's, this is fraught with taboos, and danger. I loved her spirit, and her conscience.

Wolf also grapples with the ethics of war. He would much rather not kill anyone. But when he faces the realities of what Jews are dealing with in Europe, can he turn a blind eye to their suffering? He is also feeling conflicted about his romantic feelings toward his childhood friend, Max. Again, we are reminded that being Gay was not just frowned upon back then, but illegal.

I loved that there were not one, but several gay characters, as well as African-American characters, in this book. These were multi-faceted people who were not solely defined by one trait.

The plot has many twists and turns that kept me reading well past my bedtime! Like any good mystery, there were clues and foreshadowing that the reader could glean. But, when some of the twists were revealed, it was yell-worthy (which I did do, loudly)!

The book had a sense of urgency throughout that I thought worked really well to convey how all encompassing the war was for everyone. Not only life, death, and freedom hung in the balance, but also ethics, at both a personal and national level. Are we willing to kill for our country? Are we okay with creating weapons that can kill millions? What are our responsibilities?

As I looked over other reviews of the first book on Goodreads, I was not alone in feeling that The Girl With The Red Balloon ended abruptly. Not so with The Spy With The Red Balloon. The author takes time to really explain what happens to the characters. Since I was so fond of Ilse and Wolf (plus their various love interests) by the ending, I was really pleased to know how most of the characters ended up! This was so satisfying.
Profile Image for Shannon (It Starts At Midnight).
1,189 reviews1,020 followers
October 12, 2018
You can find the full review and all the fancy and/or randomness that accompanies it at It Starts at Midnight


Wow, this book is good. It's a companion to  The Girl with the Red Balloon , and it's absolutely just as strong as its predecessor. Which is a hard feat, because I loved its predecessor, so. The only minor qualm I had was that a few things were a bit predictable- but honestly, it didn't really dampen the impact of the story, so whatever. So let's go ahead and talk about the stuff I loved!

The Things That Made This Book Awesome:

•The time period. Look, a book set (and done right, which this certainly is) in WWII era is probably going to pull at the heartstrings. This certainly did.

•Ilse and Wolf are incredible characters. Not only were they each incredibly sympathetic and well developed, but their sibling bond was incredible. It was also really believable, which is hard to accomplish. These two didn't want to be separated, but in the end, it was really good for each of their personal growth. Of course, their bond never faltered either, so it really was the best of both worlds.

•There was light in the darkest of places. Truly, it gives me hope for our world now. It's lovely to see acts of selflessness and bravery and goodness in such bleak and desperate times.

•It's incredibly emotive. There is so much going on that really made me feel things. Not only is the obvious horror of the war raging on in Europe, but even in Ilse's American small town, the awfulness of racism and homophobia is everywhere. You can't help but feel angry, sad, and scared for these characters.

•The tension and the stakes are, for obvious reasons, incredibly high. This book keeps the action coming, because of course it has to. There is so, so much on the line, and everyone involved knows that it is so much bigger than just themselves. It makes for a very powerful novel, to say the least.

Bottom Line: Honestly, if you are even considering picking up this series (you can read them alone or together!) I implore you to do it. It's fabulously written with characters who you won't be able to forget. The messages it delivers are timeless, and so incredibly important. Do the thing.
Profile Image for Dani.
98 reviews17 followers
August 26, 2018
By far one of THE best books I have ever had the pleasure of reading. It was thrilling, suspenseful, heartbreaking and heartwarming all at once. I won't lie, I was scared as hell the entire way through, but each character and each part of this book have left an imprint on my heart and I am so glad I was able to read it. I can't even imagine the research that went into this book.

I don't even know what else to say. It's a book that, once it's finished, leaves you a little speechless. Thank you for the work you put into it and for sharing it with us; it was magical.
October 16, 2018
I received a copy of The Spy with the Red Balloon from Netgalley. I had heard a lot of good things about the first book in this companion series The Girl with the Red Balloon, which I have unfortunately not had the time to read yet. They are both historical fiction novels set at the time of World War II, that have magic in it, and Jewish main characters.

This book is #ownvoices for Jewish representation.

Check out my book blog for more book reviews and other bookish posts!


While reading this, I kept thinking, why had I not read The Girl with the Red Balloon yet!? The book was so good, and I’m definitely getting the first one. Since, I hadn’t read the first one, I can say that The Spy with the Red Balloon works as a companion novel. You understand everything without needing additional knowledge from the first book.

The story shows the brutality of Nazi Germany without describing every evil in detail. It focusses a lot more on what Ilse and Wolf are doing to help and how their life continues during the war.

Katherine Locke closes up the plot-hole of why not all of the victims were saved, if some people had magic, by explaining that the magic was tied to blood, and the magic users would need to have a lot more blood than they could give to save everyone.

The main characters are siblings, and they had such a lovely relationship. They took care of each other, even from afar. It was lovely to find out that both of them were queer, usually books seem to think that there can only be one queer person in a group of siblings, which is just ridiculous. I do head-canon Ilse as aro-spec, and I’d be interested to see if this is the case. They are also quite different from each other, and contrary to popular gender stereotypes, Ilse is a scientist, while Wolf becomes a spy.

One of the major scientist characters is a black female scientist. Through Stella’s story, the reader realises that even though Jewish and black people both experienced discrimination, the communities were affected in different ways. Stella also makes the reader aware that just because a place thinks that it is not racist, doesn’t mean that that is the reality.

I especially loved how the four scientists (who were all women) became closer to each other, and started to help each other out. It’s lovely to read about friendships between women, where the women are accepted for who they are.

The aroantagonistic phrase of “just friends” is used at least twice.


You should definitely get this book. It’s soooo good! I will definitely be reading The Girl with the Red Balloon soon. It was beautiful to read a book that focussed on sibling relationships and friendships between women.

Trigger warnings: violence, Nazis, Holocaust, death.
Profile Image for  Aυѕтιη  .
110 reviews3 followers
December 24, 2020
A rare non-ARC review, here we go.

After reading THE GIRL WITH THE RED BALLOON, which had the absolute audacity to give me Feelings, I went into this companion book (not a sequel, not really a prequel) with high hopes and the author delivered.

THE SPY WITH THE RED BALLOON follows two queer Jewish teenagers with magic in their blood (literally) who come to the attention of the United States Army during World War II. Wolf ends up on a secret mission on the ground in Germany, while Ilse, a brilliant physicist, is recruited with three other girls to apply their knowledge of science and magic to a secret government project. There is a good balance of energy in the story as it alternates between the two points of view as a spy appears in the midst of Ilse's project and Wolf's plane gets shot down before the drop point for his mission.

My hatred of WWII and Holocaust books is broad, multifaceted, and a rant for another time. However, Locke does it perfectly because although Ilse and Wolf are Jewish this book is not the umpteenth book about Jewish Suffering During The Holocaust. This is a book, to quote the author, about "Queer Jewish Kids Punch Nazis While Doing Science and Sabotaging Hitler". The characters are comfortable in their Jewishness but just coming to terms with being queer in a society that, war or no war, is not okay with that. And while this book is largely centered on work to prevent Hitler from developing nukes, in the two scenes that touch on the broader impact of the Holocaust, Locke explicitly includes the fact that queer people were put in concentration camps too. In fact at one point, Wolf punches a Nazi and then informs him that he was punched by a queer Jew.

Good times.

Anyway, I highly recommend this book and its companion to basically everyone who's ever read a WWII/Holocaust book because it provides perspective and dimension to a very important part of history. It isn't tragedy porn, it's serious and thought-provoking without being depressing, there is no Bury Your Gays (), it involves the line "Get in losers, we're blowing up Nazis". What else could you really want?
Profile Image for Kira.
153 reviews12 followers
March 12, 2020
Fighting Nazis with blood magic! Gay teens in the 40s! The Manhatten project but with magic! Small! Changes! Make! History!

This book made me cry quite a lot. It's in WW2, obviously people are going to die and bad things are going to happen, but also little bits of hope! I need to go read The Girl with the Red Balloon now.
Profile Image for Priya.
1,510 reviews36 followers
January 22, 2022
I loved the sibling bonding the most and the plot set in the middle of WW2 was intriguing with a mix of science, magic, fantasy.
Loved the friendship between Ilse and the girls she worked with in the lab.
Just thought it could have been a little shorter than it ended up being!
Profile Image for JoLee.
1,568 reviews59 followers
November 1, 2018

Featured in World War II Wednesday on Intellectual Recreation.

Last year I read Katherine Locke's The Girl With the Red Balloon, and it made me really curious to learn more about the magical balloonists of the past. Well, I got my wish. In The Spy with the Red Balloon, Ms. Locke takes us back about 45 years to World War II.

The story stars siblings Ilse and Wolf. They are recruited to help the war effort with their magic. Wolf is sent overseas as a spy, and Ilse become part of the Manhattan project, working on a way to deliver the atomic bomb with magic.

There are some really intriguing things about this book. I do enjoy a good alternate history, and I'm going to slot this one in with other great alternate World War II novels like Wolf by Wolf and Front Lines. I really like the way science and magic overlap in the Balloonist series. I also really enjoyed the sibling relationship between Wolf and Ilse. I was completely on board for the relationship between Wolf and Max. However, I thought Ilse's romance was underdeveloped and frankly unnecessary. Sometimes YA books it feels like there's a need for every character to pair up, and that can feel forced. I would have loved more of an emphasis on Ilse's female friendships.

All in all this book has a fun combination of science and magic, daring rescues, lots of danger, questionable morals, LGBT romances, and familial love.

Review copy from NetGalley.
Profile Image for Ashley.
578 reviews61 followers
April 11, 2019
ahhhh this was so good. I love Ilse and Wolf so so much

I'm coming to realize historical fantasies are one of my favorite genres. I love how magic and weave between true historical events (the research it must have taken!!!) I read these out of order so will 100% be reading the girl with the red balloon whenever I can get my hands on it.

You should read this book because:

- queer jewish siblings fighting nazis (!!!!)
- very cool magic system based in blood + science
- demi rep!
- balloons! with magic!
Profile Image for Annalee.
119 reviews6 followers
August 31, 2018
This book was just as good as it's companion novel, The Girl With The Red Balloon. I loved how realistic this book was and how it made the magic seem possible. The writing style was brilliant and I can' t wait to read more by Ms. Locke. The characters were also very well written and I loved them with all of my heart. The plot was very intense and I was kept on the edge of my seat the whole book.
Profile Image for Sarah.
862 reviews69 followers
August 25, 2019
I loved this even more than the other Balloonmakers book in the duology (which I loved an awful lot). Queer Jewish magicians in WW2 and one of them is a science genius yes yes yes y e s ♥️♥️♥️

PS: For my fellow DoE nerds, half of the novel takes place at Oak Ridge, TN, and now that I've finished the book, I ain't even mad they didn't go to New Mexico. It worked out!
Profile Image for jilly (taylors version).
45 reviews1 follower
January 6, 2022
I liked this book, got hooked onto it right away, and overall i would rate it about 3.75 stars, its an overall good read and katherine locke is such an underrated author. I loved Ilse and Wolf's characters, aswell as all of their friends. I was very upset when certain deaths came about. Impressed with the work and would read again.
174 reviews1 follower
October 3, 2018
I was so excited to read this book because I adored The Girl with the Red Balloon; and this prequel is rich in history, magic, troubling grey areas, and beautiful language in the same way. The unique thing that I love most about it is the sibling relationship between Wolf and Ilse--their closeness and their clashes and similarities and perceived inadequacies and deep understanding and constant sniping. It's a relationship that gets you invested right away. And as comforting and familiar as it initially is, it has to evolve in difficult ways as they are separated for the first time in their lives and have to pursue their own storylines, their own relationships. Some of the ways they each change during the war are heartbreaking. And, knowing what happens in The Girl with the Red Balloon, you can see how the effects of their changing will ripple outward, and how they might make mistakes they wouldn't have before. But their relationship doesn't *weaken*, and that ends up feeling like reason for hope.

Their other relationships are compelling in and of themselves, too. I'm particularly attached to Stella, the delightfully dry and practical genius who is also the lone black woman in the group of magic-users assembled around Ilse (and I appreciate that the other women's respect for and friendship with her doesn't get anyone a free pass on allyship); Lily, the MI6 operative leading Wolf's mission, who is a badass and hasn't had to have all her femininity and softer feelings stripped away to make her into one; and Max, Wolf's lifelong best friend with the potential to be something besides a friend. I would have liked for Max to be developed more, actually, as his own person; but it was nice to eventually get to see him from Ilse's POV, and be reminded that he exists outside of Wolf's perception in ways Wolf doesn't even think about.

The first-person narration manages to convey the adolescence and...*siblingness* of the characters while also feeling oddly literary; I like that about Locke's style. This book definitely feels of a piece with The Girl with the Red Balloon. There are a couple deliberately anachronistic lines, but they're so damn satisfying that I can't bring myself to mind. Most of them have to do with punching Nazis.

Some of the morality in the book is a bit more uneasy than Nazi-punching, which is to be expected of a story dealing with the Manhattan Project. On that front, the book is definitely aware of the moral dilemmas. It's even aware of the issues with being too black-and-white about anything--not that certain things aren't irrefutably wrong, but that rigidity and idealism can both cause problems down the line. Like Girl with the Red Balloon, though, it chooses to be less aware of certain things. Sometimes it's sticking to the constraints of the time period, as with the few mentions of Israel--the characters in the midst of the Holocaust are thinking of safety, not the horrifying situation Israel will eventually become, but the latter is always at the edges of my mind. Sometimes it just feels like something's been forgotten, as when the leader of the nascent balloonmakers says he hopes their rescue services will never be needed in America, which has in fact been rounding up its own citizens in concentration camps on the basis of ethnicity for a year by the time the book starts. These moments made me uncomfortable, but I also don't feel like I can blame the characters for having their all their focus taken up by the Holocaust.

I'm also rather emotional about how this book deals with its characters' Judaism, since it's central to the Jewish characters' identities and to the setting itself but each of them has a different relationship to it, and it's only one part of some very complicated patchworks...I have trouble articulating my emotions since I'm still working on articulating my own relationship with Judaism, but I really, really appreciate that Locke's unapologetically and complexly Jewish books exist.

My final note is about the queer rep--it's here, and it's lovely. Again, it varies between characters and is only part of the patchwork. The dangers of queerness during the 1940s are present, and some characters may be held back by that while others fail to really understand someone else's fear; they're all working on it, but the focus isn't on fear or tragedy but on kids figuring out their feelings and their identities. And I'm especially gratified by the asexual rep we get in Wolf.

Overall: The Spy with the Red Balloon is beautiful and gripping (I read it faster than anything I've read in the last several months) and you should read it! Probably after The Girl with the Red Balloon, for the full effect of the worldbuilding.
Displaying 1 - 30 of 129 reviews

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