Thanks to NetGalley and Atria Books for providing me with an eARC.

Wow. This was not what I expecting. I enjoyed this more than I thought I would. This reminded me so much of Addie LaRue and the Midnight Library but better. This is the first time travel romance that I've read and actually liked. The timeline switches were super smooth and at one point in the book everything clicked into place, especially some of the smaller things like habits and mannerisms from before start to make sense. The characters were also well fleshed out and I really liked the ending. The writing was beautiful, especially for a debut novel. Honestly, I have nothing to complain about. Overall, this book had great plot, characters, romance and atmosphere all at once. I would absolutely recommend. I'm so glad I chose this for NetGalley Camp.

🌅 Thank you to NetGalley, Simon & Schuster (and Atria Books) for the ARC in exchange for my honest review. The opinions expressed are entirely my own.

Some books pull you in gently, and others grab hold from the first page and refuse to let go—The Book of Lost Hours did the latter for me. It’s a richly imagined, beautifully written debut novel that blends magic, memory, and time in a way that feels both timeless and urgent. It was described as appealing to readers who love books like The Ministry of Time, The Midnight Library, or The Invisible Life of Addie LaRue, which appealed to me. I would add that if you’re craving something fresh with deep historical threads, this one is for you.

The story follows Lisavet Levy, a young woman who discovers a hidden world where time can be accessed, altered, and—if you’re not careful—lost. Through an ancient and mysterious library that exists outside the ordinary flow of time, Lisavet embarks on a journey that spans centuries, memories, and choices she never imagined she’d have to make. Along the way, we meet other key characters whose lives, loves, and heartbreaks intersect with hers in ways that slowly, masterfully unfold. The novel explores what it means to carry history with you, the difficulty of impossible choices, how the past shapes the present, and who has the power to remember—or to forget.

While the book plays with time travel, alternate realities, and a hint of magical realism, at its heart, this is a story about human connection, longing, and the weight of memory. There’s romance here too, but it’s not the light, fluffy kind—it’s quiet, yearning, and bittersweet. Every chapter left me wanting more, not just to know what would happen, but to stay a little longer in this beautifully crafted world.

Hayley Gelfuso’s writing is lyrical without being flowery, though I will say the pacing may feel slow, especially early on. The chapters can run long, and there were moments where the prose veered into being a touch too wordy, making it slightly more challenging to stay fully immersed. That said, once the story hits its stride, it’s nearly impossible to put down—the emotional payoff and thoughtful plotting more than make up for the slower start. This is not a book for readers looking for a fast-paced adventure; it’s for those who enjoy stories that unfold like a puzzle, where every piece matters.

Content-wise, I’d offer gentle warnings for grief, discussions of death, and existential questions around identity and time. There’s nothing graphic or gratuitous, but the emotional intensity may resonate deeply for readers who’ve experienced loss or who find themselves reflecting on “what could have been.”

One of the things I loved most about this book is how it reflects on who gets to write history—who is remembered, who is forgotten, and how time can be both a gift and a burden. It’s a novel that doesn’t just tell a story; it asks big, meaningful questions without ever losing its heart or crossing into the realm of becoming preachy.

In short, The Book of Lost Hours is a spellbinding novel that lingers long after the last page. I highly recommend it to readers who love immersive, character-driven stories with a touch of magic, a dash of romance, and a whole lot of soul. I’ll be thinking about Lisavet and her world for a long time to come—and I can’t wait to see what Hayley Gelfuso writes next.

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,This gave the story a unique perspective.

I loved reading Lisavet’s and Ernest’s love story, although I felt the story was better portrayed from Ernest’s POV. Lisavet’s character lacked a little of the angst that I think would have gone so well with her character.

Moira’s character stole the show for me. Her character had a lot of depth that I felt was lacking with Lisavet, and she stole the show for me. I also liked that the struggles she faced were relatable to real-world examples.

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.

Special thanks to NetGalley and the publisher for a free, electronic ARC of this novel received in exchange for an honest review.
Expected publication date: Aug. 26, 2025
“The Book of Lost Hours” by Hayley Gelfuso is the ideal read for fans of “The Midnight Library” or “The Invisible Library”.
In 1938, Lisavet Levy’s father is captured by the Nazis and, to keep her safe, he puts her in “the time space”. The time space is the magical in-between where human memories are stored, captured in books by “the timekeepers”. Trapped without means of escape, Lisavet finds herself wandering through the immeasurable rows of books, where she finds timekeepers destroying books, and the memories they contain. In her quest to uncover why certain memories are being destroyed, Lisavet disappears without a trace.
In 1965, Amelia Duquesne is grieving the loss of her beloved uncle, Ernest, when she is approached by a CIA agent who asks for Amelia’s help in retrieving a book. The book once belonged to her uncle and hasn’t been seen for years, but the secrets it contains could cause utter chaos, chaos that the CIA wants to avoid at all costs. But the book is in a magical place called “the time space”, and Amelia knows it’s risky to enter, but will her curiosity get the better of her?
Gelfuso’s “Hours” is a dual-timeline novel, narrated by Lisavet, in 1938 and Amelia, in 1965. The “CIA agent”, Moira, also has her turn at centre stage, as she helps readers understand the secrets of the time space. All three characters have a deeper connection than it appears, although it isn’t that difficult to figure out what that connection is, so it doesn’t come as much of a surprise when it’s revealed. However, that doesn’t contribute in any way to the overall entertainment value of this novel.
The time space was a fascinating and unique concept. A library of memories of sorts, where you can spot the occasional spirit caught between worlds, where timekeepers store and destroy human memories, changing the outside world in an instant. A complicated imagining, but Gelfuso manages to explain the illogical physics of the time space in a digestible and generalizable way.
In “Hours”, there are timekeepers and there are “rebels”; one group who wants to destroy certain memories and the other who believes all memories are sacred and want them all to remain safely stored away. Neither side is the “bad guy”, per se, as they both have logical reasons for doing what they do, but it can be a little difficult to keep track of who is on which side (especially when certain characters play both sides, or start on one side and then switch).
“Hours” is charming, intelligent and imaginative and I thoroughly enjoyed the immersive plot and likable characters.

⭐️⭐️⭐️⭐️ 4 stars

First of all, this book has one of the most original concepts I’ve read in a long time. Time travel, memory magic, Cold War spy vibes, and a hidden archive of memories that exist in a secret library only accessed with enchanted watches? Yes, please. Gelfuso came out swinging, and I was absolutely here for the premise.

We follow two timelines: Lisavet in 1938 Germany during Kristallnacht and Amelia decades later in Cold War era America. Their stories are connected by more than just time and trauma, they’re linked by the fate of the Time Space itself, and what happens when the power to rewrite history ends up in the wrong hands.

Lisavet stole the show for me. She’s gritty, complex, and just so real. Watching her transform from a victim of Nazi cruelty into someone who reclaims her story, even when it costs her everything? Gut wrenching and powerful. Amelia's storyline was less emotionally intense but still added depth to the bigger picture. The romance subplot didn’t overpower the plot, though it did feel more one sided at times.

The writing itself is beautiful and immersive, some passages read like poetry. But I will say, the pacing slowed down for me near the end. It dragged a little when it should’ve been punching me in the feels. And while I loved the worldbuilding, I do wish a few more rules of the Time Space had been spelled out. It leaned heavier on the magic and emotion than the technical "how it works" side, which is fine for some, but might frustrate readers wanting strict time travel logic.

This book reminded me of The Midnight Library meets The Ministry of Time, with a little espionage and romance mixed in. It’s not all sunshine, it deals with deep loss, the ethics of erasing memories, and who gets to control our stories. Heavy stuff, but told with heart and intention.

Final Thoughts:
Original, emotional, and thought provoking. I closed the final page feeling a little haunted, a little hopeful, and a lot impressed. A solid 4 star read for me, and I’ll definitely be watching what Gelfuso does next.

“The Book of Lost Hours” was a very enjoyable and creative book. The story is thought provoking, as one of the main elements of the story is the ability of select individuals to enter “time space”, where they can “erase” memories that they (or the government on which behalf they are working) deem “dangerous” and want forgotten. This has real-life analogs in book bans, censorship, “alternative facts”, etc. However, to some extent, it is a fundamental aspect of human existence. People don’t have the capacity to remember everything, so they must prioritize what to remember. Also, for much of human history, knowledge was passed down orally or, if written down, the ability to read and write was limited to a small number of people. And of course, those in positions of power and influence can dictate, to some extent, what information is preserved and how past events are remembered. It makes one wonder how much of the past we don't know or truly understand based on what "memories" were saved.

The story starts off in Germany on the eve of WWII, when Nazi timekeepers are erasing memories that they want forgotten, and later shifts to the 1950s and 1960s and Cold War tension between the US and Russia, where timekeepers are erasing memories to help promote their country’s view of history.

Interfering in these efforts is Lisavet Levy, the daughter of the last watchmaker with the knowledge of how to create the watches that allow entrance to time space. Lisavet is trapped in time space and is seemingly not bound by the same time constraints as others. This makes her a person of interest to the CIA (and the KGB) when they discover she is saving and hiding memories or fragments of memories they have tried to destroy.

Lisavet and the book in which she stored the salvaged memories will eventually disappear. It was an American timekeeper, Eugene, who discovered and befriended Lisavet, but also who brought her to the attention of the CIA’s Temporal Reconnaissance Program (TRP). After Eugene’s death, Moira, the director of the TRP, will attempt to enlist the aid of Eugene’s niece, Amelia, to find Lisavet’s lost book of memories. Amelia will make a number of unexpected discoveries that will call into question the motives of Moira and the TRP but also will fundamentally alter everything she thought she knew and understood about herself and her family.

The story has plenty of twists and turns that will keep the reader guessing. Some readers may puzzle out the connection between certain characters before the author reveals them but for many readers it will likely come as a surprise.

This was so much fun to dig into! Magical and entertaining, this dives in and takes a closer look at the human condition.

I am absolutely in love with this book. I read this book one sitting. I was hooked from the first chapter. There is such rich and intriguing world building. I love the characters especially Lisavet. The love story between her and Ernest is absolutely one of my favorites. The aspect of time traveling through memories is just so intriguing and unique. I highly, highly recommend this book. I’m so glad that I was gifted a copy of the book.

⭐️⭐️⭐️⭐️ / Out of 5 Stars ⭐️

Genre/Tropes ✨Historical Fiction, historical romance, secret agency, time traveling

Thank you to NetGalley for the chance to read and review this book for Camp NetGalley!

No spoilers here, but I wish this book had been more fleshed out. I would have appreciated more descriptive scenes, how the characters moved, what they thought. Unfortunately I just didn't feel the "magic" that comes from a story with timeline switching.

I fell into this book and couldn't stop reading. I liked the dual POVs and felt that all the characters were very well written..
This book is so well written and draws you into this story of time and memories.
Lisavet and Ernest have such a beautiful love story that goes through time as it continues to connect them.
Amelia is connected to all of it and is such a strong character herself.
I caught on to who Moira was and understand as a mother wanting to do everything, even changing time and memories to protect her child.
Some things were predictable but the story keeps you guessing and wanting more.
A great book for book clubs, as there is much to discuss.

Thanks NetGalley for this ARC.

Thanks

This book is about the importance of books and libraries, and time and memories.

"But you just said you're a memory. You can't be real."
"Why not? Memories are the realest thing any of us have."

Gorgeously written, sweeping narrative, with interesting character development, and a resolution both expected and entirely unexpected. A literary triumph.

"Time was an illusion and memory even more so. In this life, she was happy."

OK, this post is going to be filled with SPOILERS, but it's the only way I can fairly review this book.

First, I totally understand why the book is considered a smash-up of The Midnight Library and The Ministry of Time, but I would throw in Interstellar because of the parent-child dynamic and the willingness to bend time to preserve it.

I like all things time travel and a story wrapped around the middle part of the 20th Century was a great construction. The "lovers in all possible universes" was rewarding to the reader, though I have to admit I figured out who Moira was pretty early on.

Fair warning to one and all: keep track of the dates at the beginning of each chapter as they jump around a bit. This is not a flaw in the storytelling, just sometime to keep front of mind for the sake of your own sanity.

That said, I liked themes of sacrifice, lost love and rediscovered love. The mirroring of the relationships between Lisavet and Ernst and Amelia and Anton were well played and the ending was more satisfying than I expected.

Chapter 24, however, I'm still not sure about. And I am curious what historical events where "changed" because time had not been tinkered with (too much of For All Mankind is probably swirling around in my head).

The Book of Lost Hours is a good read told at an enjoyable pace that keeps you wanting to read just one more chapter.

I received a free DRC of this book through Netgalley. Lisavet grows up in a safe space outside of time thrust there by her father before the Nazis killed him. But she was mostly on her own until she falls in love with one of the timekeepers. To protect him, she had to let him go, but will the others let her go? The story travels back and forth between different locations and times as we find out how time and memories can be manipulated. This is a book that you need to pay complete attention to with all of the jumps in time. It had some interesting premises about how time and memories work. It's good to look for the helpers especially in times of crises.

What an interesting and often philosophical take on time and dimensionality and what the value of human experience and collective history is in the form of memories.

There are two main timelines: 1930s-1950s and 1960s.

To save her from the Nazis on Kristallnacht, Lisavet's father pushed her into the Time Space where memories are held within books for each person. Her father is a watchmaker whose time pieces allow one to travel into the Time Space. In there, Lisavet spends multiple years preserving memories into a book after seeing government agents entering in and out to delete the memories that serve to maintain the collective memories of their political agendas.

The second timeline is of Amelia who has lost her uncle Ernest who raised her after her mother passed away. Amelia is caught up with Moira who is part of the CIA who has enlisted her help in recovering this book that Lisavet had. Amelia's uncle was one of the government agents who had met Lisavet in the Time Space.

There are a lot of twists in this story which were predictable but nonetheless interesting to read.

Thank you NetGalley for the opportunity to review this book! #CampNetGalley

this book was so, so good! i loved how big the plot felt without ever getting confusing, and it kept surprising me over and over again. watching all the different storylines click into place was really satisfying, and you can tell how intentional every part of it was.

the character dynamics were genuinely so well done, and the couples in this story were so top tier. the writing was beautiful but still easy to sink into, and the pacing made it hard to put down! this is the kind of book that reminds you how good it feels to get lost in a story!! definitely recommend :)

thank you to netgalley and atria books for the arc!

This was such an interesting and entertaining read! I really enjoyed all of the POV's and felt like the characters were unique and developed. The multiple timelines were done super well and I had an easy time following the story! It felt wordy at times, but there was always plot progression taking place. After the 45% mark, everything fell into place and the story truly took off.

I enjoyed the historical setting of this book. The current events that were taking place at this time were not directly mentioned much, but the characters' actions and opinions felt very fitting to the time period. I also think the detachment from major current events from Lisavet made sense considering she lives most of her life in the form of others pasts.

I do think the romance felt like the most obvious plot point. It was really well done though, and I felt myself caring about the happiness of the characters and hurting with them as they worked through their struggles. This applies to not only this book, but many others that have been released over the years: Romance does not detract anything from main or deeper-meaning themes just because it's included in a novel. It simply makes it easier for many readers to connect with the story and subsequently digest heavier topics that can be threaded throughout.

The overarching theme was beautiful and felt very fitting with today's censorship, biased media, and the extremely active political attempts to skew history. 1984-ish vibes; "Who controls the past controls the future. Who controls the present controls the past." The ending was a very full circle moment that tied things up neatly while still leaving the reader with the sense of endlessness.

ARC provided for an honest review.

The Book of Lost Hours is a timeline traveling story of a young girl, Lizabet Levy, who has grown up in the space between time because she is unable to return to the usual timeline. She learns secrets of the Timekeepers and of time itself, and this lovely story unfolds a tale of love, patriotism, and the nature of memory itself. It gives off a fairy tale vibe throughout the whole novel.

This book would be an excellent pick for someone who loved The Secret Life of Addie La Rue or The Timekeeper’s Wife and similar novels that bend the boundaries of reality and time. Thank you to Atria Books for providing this book for review consideration via NetGalley. All opinions are my own.

I just got this yesterday and I'm already finished!!!! I love the whole story. Books and libraries, memories and mystery all in one! I couldn't put this down until I got to the end.

Not quite what I was expecting, but I went it blind and wasn't disappointed, this is a blend of gothic, historical fiction and fantasy. I read it fairly quickly over two days, but definitely worth it and a solid read for 2025. .

Thank you NetGalley and Atria Books for an E-ARC of The Book of Lost Hours!

Wow, wow, wow! Genre-blending, heart pounding, thought provoking, emotional, this novel has it all and will stay with you long after you have finished. I loved the historical fiction aspect of this novel, while also telling a love story, and providing a thrilling mystery.

The characters are extremely well developed, and I found myself sharing in their joys, as well as sorrows. Hayley Gelfuso drew me in from the very first page and I did not want the journey to end.