Grateful to #NetGalley for the ARC!

The secrets of the time space are kept by lineages of watch-makers, who are capable of accessing the massive library holding the memories of all those who have died by opening portals using magical watches. Lisavet Levy's father was one such watch-maker and on Kristallnacht, he hides his daughter in the time space before he is murdered. While in the time space, Lisavet witnesses soldiers destroying memories to rewrite history and makes it her mission to preserve as many memories as she can. In 1968, Amelia Duquesne is an orphan who had been in the care of his uncle until his untimely death. After his funeral, a woman who had worked with her uncle comes to Amelia to teach her to use the watches to enter the time space and to find the book her uncle had been searching for.

This book had a unique premise and the time space was incredibly imaginative and vividly described. The book is entertaining and the plot moves quickly. This reads a bit like a YA or new adult novel to me, in that it very focused on the action on the page and it made for a very quick read. I think this book would be an excellent beach or vacation read!

Hayley Gelfuso's "The Book of Lost Hours" is an absolute masterpiece, a truly immersive and unforgettable reading experience that earns every one of its five stars. From the very first page, I was completely captivated by Gelfuso's exquisite prose and her remarkable ability to weave a tale that is both deeply personal and sweepingly epic.

The premise alone is intriguing, but it's the execution that truly shines. Gelfuso crafts characters who feel incredibly real, their joys and sorrows palpable on the page. I found myself rooting for them, grieving with them, and celebrating their smallest victories. The intricate plot unfolds with a masterful pace, revealing layers of mystery and emotion that kept me eagerly turning pages late into the night.

What truly sets this book apart is Gelfuso's evocative world-building. Whether she's describing the dusty corners of an ancient library or the vibrant pulse of a forgotten city, her descriptions are so vivid you can almost taste the air and feel the textures. This rich tapestry of settings serves as the perfect backdrop for a story that explores profound themes of time, memory, loss, and the enduring power of connection.

"The Book of Lost Hours" is more than just a story; it's an experience. It’s a book that will linger in your thoughts long after you've read the final word, prompting reflection on your own lost hours and the moments that truly define us. If you're looking for a novel that is beautifully written, emotionally resonant, and utterly compelling, do yourself a favor and pick up "The Book of Lost Hours." It's a journey you won't regret.

The Book of Lost Hours by Hayley Gelfuso is an astonishing, genre-blending achievement, equal parts emotional, cerebral, and spellbinding. A masterclass in dual timelines and narrative cohesion, this book weaves together elements of science fiction, magical realism, historical fiction, and ethical inquiry, all through the deeply human lenses of love, family, survival, and sacrifice.

Told across multiple decades and perspectives, the story never loses its grip on the reader. The dual timelines are executed flawlessly—distinct, emotionally resonant, and interwoven with revelations that land with impact. The transitions between timelines feel deliberate and rewarding, with each chapter adding depth and clarity to what came before. If ever a novel begged to be adapted into a limited series, it’s this one.

At the heart of the novel is a fierce and resilient female protagonist who grounds the more fantastical elements of the plot in something deeply real: her fierce protective love. Her strength is never performative—it’s quiet, feral, and believable, and she forms the emotional backbone of the story. The characters across generations are fully realized, making the book not just a time travel epic but an exploration of how legacy and love reverberate through time.

The science is a triumph here. Gelfuso makes the theoretical feel intimate and the complex feel coherent. The time travel mechanics and ethical ramifications are explained in a way that’s accessible without ever being dumbed down.

What truly elevates the novel is Gelfuso’s writing and pacing. She trusts her reader. Hints are scattered subtly but meaningfully, and the reveals never feel forced, they’re crafted with elegance and layered intention. The story doesn’t hinge solely on its twists, but rather how each revelation reshapes the emotional core of the narrative..

For readers who like:
-Dual timelines
-Historical fiction
-Strong, complex female leads
-Intergenerational stories of love and loss

Final Verdict
The Book of Lost Hours is a devastatingly beautiful novel that balances science and magic, intellect and emotion. It’s a love story wrapped in a time loop, a reflection on the consequences of our choices, and a powerful exploration of legacy. Hayley Gelfuso has written something unforgettable and with just one book, she’s earned a spot as an auto-buy author on my shelf.

Grateful to NetGalley, Atria Books and Hayley Gelfuso For the opportunity to read an advance copy of this story in exchange for an honest review.

Heartbreaking and beautifully intriguing story about time and memories. Two women, connected by a secret library containing all the memories of time, try to stop the destruction and loss of important memories. I can't stop thinking about the characters. I love stories about secret libraries and their keepers.

DNF @ 60%. I honestly just don't care what happens in this story. I liked The Midnight Library well enough, and LOVED The Ministry of time; both are comps for this book, and while I can see why those were comped, this isn't as good as either of them. All of the characters come across as very flat and the emotion is sorely lacking from the story, which makes the stakes seem incredibly low when they should actually be incredibly high. Gelfuso hasn't succeeded in writing romantic tension OR suspense tension, both of which this story should have in spades. I do think she has struck on a good way of doing a time-travel romance, which is having the romance take place outside of time itself, but the rest of the story just isn't there.

I read The Book of Lost Hours in one sitting. I had to know how each timeline connected, how the characters fit together, and what the hell was actually happening in the time space. Hayley Gelfuso is a master storyteller. She doesn’t just write—she weaves. Every thread matters. Every choice lands.

Lisavet broke my heart. Eleven years old, hidden in a library of memories while the world outside burns. Her father disappears, and she’s left to wander through other people’s pasts. Years go by. She learns that timekeepers are slipping in and erasing memories. She decides to fight back.

Then comes Amelia in 1965. Her uncle is dead. The CIA shows up with a strange book and a mess of secrets. Amelia doesn’t know who to trust, but she knows something isn’t right. Her story could’ve felt distant, but it doesn’t. It aches in the same places Lisavet’s does.

This is a time-travel story. A memory story. A love story. It’s about who gets to decide what’s remembered and what gets erased. It’s about survival and resistance and finding your way through the wreckage.

I couldn’t put it down. I didn’t want to.

The Book of Lost Hours is a dark, atmospheric fantasy novel that blends gothic mystery with themes of grief, magic, and self-discovery. Hayley Gelfuso’s writing is lyrical and immersive, pulling readers into a richly detailed world where every shadow seems to hold a secret.

The story centers on a young woman grappling with loss, as she uncovers hidden truths about her family and herself. The magic system is unique and haunting, revolving around time, memory, and sacrifice. Gelfuso skillfully weaves in themes of longing, regret, and the price of power, making the emotional stakes feel deeply personal.

What really stands out is the moody, almost hypnotic atmosphere—readers who enjoy gothic tales with lush prose will likely be captivated. The pacing is deliberate, allowing the mystery to slowly unravel while keeping readers intrigued by the eerie setting and unpredictable twists.

Fans of The Invisible Life of Addie LaRue or The Ten Thousand Doors of January will likely appreciate this novel for its blend of melancholy beauty and magical realism.

In short: A beautifully written, atmospheric tale of grief, magic, and hidden secrets that lingers long after the last page.

This was such a creative and fun read. If you liked The Midnight Library, this is definitely a good fit for you. Time is almost its own character in the book, which is such an interesting concept.
Overall, this was an excellent read. I was very excited to read it, and it did not disappoint.
I would like to thank Net Galley and Atria Books for the opportunity to read this as an ARC. The ARC was provided by the publisher via Net Galley in exchange for an honest review.

I very much enjoyed The Book of Lost Hours by Hayley Gelfuso but it took me a little while to get into and isn't the fastest-paced book to read. It does raise some interesting questions about what benefit the historical narrative has and how who controls that can change the entire thing. If you loved The Ministry of Time (as I did) you might find this enjoyable.

Thanks to Netgalley and Atria for the ARC.

Kind of a spy novel with a dash of The Book of Doors.

Lisavet is shoved into a time tunnel by her father during the kristallnacht to keep her safe. But then he’s unable to come after her.

She spends more than a decade alone among the shelves of memories trying to save memories for being damaged or erased by spies from various government agencies.

While doing this she means a member of the CIA and falls in love with which makes things complicated.

I’m not usually a thriller/spy genre fan but the humanity in this story, particularly the hubris of men thinking they can and should control history.

This was such a creative and fun read. If you liked The Midnight Library, this is definitely a good fit for you. Time is almost its own character in the book, which is such an interesting concept. I loved the world building that was based around that idea, the rules she built for Time, and how she broke those rules. I don't want to give too much away, but I will say, there were some twists I saw coming, and some I didn't. Some things she brought full circle so beautifully that you just smile and go, oh. Yes that is absolutely right.

I took one star off because the end felt like it could've been wrapped up sooner. You get to those last few chapters and go, man that was the perfect way to end that. And turn the page and there's more. Then you get to the end of that and go, oh ok. Yes, that wraps up nicely. Then there's more. Lol.

Other than that, I enjoyed this book and do recommend it!

Overall, 4.5 stars. I really enjoyed this book. The concept of the time space and a library with all memories of those who have died was something I had not seen before. The time walking was a little more mainstream, as time traveling and changing the past has been a topic in many others books I have read (The Book of Doors and The Time Traveler’s Wife to name a few). However, the uniqueness came from Lisavet’s ability to immerse herself in these memories when others couldn’t, even if they had the ability to time walk. This gave the story a unique perspective.

I loved reading Lisavet’s and Ernest’s love story, and I love that the reader gets to watch them fall in love twice. I do feel that in Lisavet’s portrayal of the love story it lacked a little depth, as I felt more of the love and angst from Ernest than from Lisavet. However, when the love story is retold in Moira’s perspective you get more of that mutual admiration. I enjoyed the depth of Moira’s character that I felt was lacking with Lisavet. The ending before the time space was destroyed, when Ernest discusses how he felt that something had always been missing but he couldn’t articulate what was one of my favorite parts of the book.

One scene that I felt was slightly lacking was when Lisavet switched Amelia for Elaine’s baby. It was sad, but there was something missing. I wanted it to feel like a punch to the gut, the angst and emotion of leaving your child in hopes to give them a better life. It was almost there, but lacked that final “umph” to really drive it home.

I also feel like the real-world struggles could have been better portrayed. For example, the conflict between the Americans and the Russians, or even the Americans and Germans, was supposed to be a portrayal of the real-life conflicts happening in the 1940a and 1960s. However, it felt more like just a conflict between different time keepers. Bringing in more of the real-world conflicts would have added another layer of depth to the story.

Overall, this was an excellent read. I was very excited to read it, and it did not disappoint.

This book took me a while to get into, but once the story started coming together I got pretty invested. The time space as a setting was an interesting concept and it drew me in once Ernest was introduced. This is definitely not an uplifting story, there is a lot of heartbreak and frustration, but I enjoyed how everything was handled. I caught onto some of the twists before they happened, but the whole end sequence caught me off guard. The ending felt a bit rushed, and I’m not quite sure what to think of how everything shakes out, but it was still an interesting read!

I would like to thank Net Galley and Atria Books for the opportunity to read this as an ARC. The ARC was provided by the publisher via Net Galley in exchange for an honest review.I like speculative time travel novels, the idea of what if? This is a book about time, and memories, and what happens if they are changed. It is a difficult book to condense in a review. It is in several timelines. It starts in Germany 1938, on the night of Kristallnacht. A Jewish watchmaker hides his daughter, Lisavet, in what seems to be a closet. He plans to comeback for her, but cannot. It is not a closet, but a TimeSpace.A place where memories reside, and are kept in books. Lisavet stays there for several years, when she emerges, WW2 is over and America is in the midst of the Cold War. And an agency has been set up to control (or attempt to ) time. The book moves between the time lines, and we meet Ernest , who works for the agency, and Amelia, his niece, Anton, a young Russian who may be working against the agency , and Moira, who knows a lot more than she is saying. It is a complex book, and at times hard to follow. But it is beautifully written, and at times heartbreaking . It has similarities to The Ministry of Time and The Time Travelers Wife, with a voice all its own.

what a BEAUTIFUL book!!!!!!! this genuinely changed my life. a beautiful book about love, motherhood, friendship, and doing what’s right. I can’t believe it’s a debut novel? if you loved the time travelers wife or the secret life of addie larue, this is the book for you. love! 5 stars! def in my top 3 for the year. Thank you netgalley for the early copy!!

I used to wonder, if I could travel in time, where and when would I go and what would I change. The more time travel stories I read, however, the more I realized how dangerous it would be to muck around with the timeline—no matter how well-intentioned you are. What if there was someone worse than Hitler? Stalin? Pol Pot? What if a change meant that we never figured out a critical vaccine or cure? Playing with the timeline or the metaverse is to play god, and I realized that I really don't want that kind of power weighing on my conscience. That said, I'm still going to dive into books like Hayley Gelfuso's thoughtful and original novel, The Book of Lost Hours, every chance I get.

Lisavet Levy comes from a long line of clockmakers, but it isn't until the Gestapo shows up at the door one night in 1938 that she realizes that her father holds the key to travel outside of time. Ezekiel planned to escape the Reich with his children until everything went pear-shaped. As a last resort, Ezekiel opens a hole in time and shoves Lisavet through. Years later, a young American girl, Amelia, is approached by a strange woman calling herself Moira. Moira winds a watch, opens a hole in time, and shoves Amelia through. (There is a lot of shoving in this novel.)

Gelfuso tracks back and forth in time to tell the story of Lisavet, Amelia, and Moira and their long, strange journey through time. Unlike a lot of other time travel novels I've read, travelers can't just pop in and out of history. They can, with effort, enter memories to see history unfold through the eyes of a dead person. And these travelers can only exit our timeline if they have a very special watch, like the ones made by Ezekiel Levy. The few of these watches that exist have been snatched up and closely guarded by the world's intelligence services. Instead of changing history by altering events, these travelers can affect history by erasing memories.

There's plenty of plot—and even a love story or two—in The Book of Lost Hours, but what really attracted me to the story are the questions it asks. Who gets to decide what to erase? What happens to history when people and their ideas are forgotten? Thinking this way can lead you down a tangled path of what if that, I would argue, ultimately ends up with an unparseable snarl of causes, effects, chaos, luck, serendipity, and appalling ethical dilemmas. We just can't know how even the slightest change will affect the timeline. I wouldn't dare try to make those kinds of decisions.

Readers who love to contemplate what could be or what might've been if the historical timeline had been pruned here and there will find a lot of food for thought in The Book of Lost Hours.

I want to thank Netgalley and Atria Books for the ARC of The Book of Lost Hours by Hayley Gelfuso

Hayley Gelfuso takes the reader on an unforgettable journey to a place where time stops to exist, and memories are stored. This wonderful story is filled with mystery, suspense, intrigue and romance. Fans of the Midnight Library by Matt Haig, The Night Circus by Erin Morgenstern and the Starless Sea by Erin Morgenstern will fall in love with this book and the characters. The book has two different timelines, but the timelines are close in years and are not hard to follow.

In the beginning of the story we meet Lizavet Levy a German Jewish daughter of a magical watchmaker during the beginning of WWII. Her father makes watches that can transport people to the Timespace. The Timespace is a place where memories of dead people are stored. With this special ability, her father is sought after by the Nazi party and on the night of Kristallnacht, the Nazi are coming. Before the Nazi can come into the watch shop and take Lizavet, he uses the watch and sends his daughter through a door and into the land where time stands still. She has no way of leaving this place and is waiting for her father to come back to get her only he does not come back. This is where the story begins.

The book was entertaining and incredibly fast to read. Hayley Gelfuso creates characters that are personable and likeable. I just finished the book and miss the characters already. I would love to read it again.

Thank you NetGalley and Atria for this Advanced Reader's Copy <3

The Book of Lost Hours is the story of time, memory, and our place/role in both.

Lisavet Levy was just a child when her father put her into the Time Space to keep her safe from the Nazis. She stayed there for years, learning how to navigate her new home and coming to be a keeper/savior of memories others seek to destroy.

When a charming American man shows up in the Time Space, he and Lisavet fall further in love than either of them could have ever dreamed, and the consequences will span decades.

What I liked:
-Setting this story in the WW2 / Cold War eras
-Lisavet and Ernest's love story
-Moira's role
-The actual concept of time travel explained in depth

What I didn't like:
-The trope of "he can't possibly understand what this means, so I'll just make this decision for him without even asking"
-The very end was kind of confusing?
-Jack >:(

Rating: 3.5 stars / 5

3.5 ⭐️.... I really love the concept of this book. Unfortunately as much as i like time travel it fell flat for me. Some chapters kept my interest while others made me fell asleep 😬.... The lenght of chapters drew me off as well and i couldn't connect with the characters . The book cover is chief kiss 😘👌...... Hoping to read your next novel in the future 🙂

This was an astoundingly good debut! It was one of my top 10 reads of the last few years. Beautifully written without the writing getting in the way of the story or anything else. I would call this light sci fi, literary fiction. My favorite kind of book. I can’t wait to recommend it to everyone I know❤️