I really enjoyed the concept behind The Book of Lost Hours, especially the dual timelines, which gave the story a nice rhythm and depth. I also appreciated that the characters weren't perfect — their moral gray areas made them feel much more real and relatable. The historical aspects were a highlight and added great texture to the story. That said, I found the mechanics of time and space a little underdeveloped, especially for a novel so focused on time travel. I was hoping for something a bit more intricate and layered. Some of the plot twists were also fairly predictable, but overall, I still found it an enjoyable and engaging read

Thank you to Hayley Gelfuso and Atria Books for this ARC.

I am not sure how I would classify this book as it has a little bit of everything, sci-fi, intrigue, historical fiction, political commentary, social injustice, romance, and some mystery. Some time travel purists might be put off by how some of the events unfold, but the book is, at times, so beautifully written that any discrepancies in the plot or theory aren’t really an issue. The multiple timeline approach and final converging point added depth to the storyline. Overall and enjoyable read.


Thanks to NetGalley and Atria for the opportunity to read this book!

This is a magical time travel novel. the characters are deep and the world building is great! The story is emotional and sweet and I couldn't finish it fast enough!

DNF. Unfortunately, this one just wasn’t for me. The plot and writing style did very little to keep my attention, and seemed very contrived at times.

Thank you to Netgalley for this ARC

I really enjoyed the overall feel of the historical element with the time-travel concept, it uses the overall feel that I was looking for and had that element that I was looking for. The characters were everything that I was wanting in this type of book and was engaged with their storyline. Hayley Gelfuso has a strong writing style and was hooked from the first page and how the end worked overall.

The Book of Lost Hours by Hayley Gelfuso is a hauntingly beautiful, page-turning novel that lingers in your thoughts long after you turn the final page. Set against the tense backdrop of the 1960s Cold War and flashing back to the final days of World War II, this story weaves historical fiction with elements of government espionage, mystery, and emotional depth.

Told from multiple perspectives, Gelfuso masterfully layers her characters’ experiences, revealing how memory, identity, and legacy intertwine. As secrets unravel and timelines converge, the novel forces readers to ask deeply human questions: Who will remember us? Are our memories worth saving? These questions are at the heart of a narrative that feels both intimate and grand in scope.

The espionage threads add a gripping edge to the story, but it’s the emotional resonance and thought-provoking themes that truly set this novel apart. With writing that is at once lyrical and suspenseful, Gelfuso captures the fragility of human memory and the power of stories to endure.

Releasing on August 26th, 2025, The Book of Lost Hours is a must-read for fans of historical fiction, thrillers, and thought-provoking literary fiction. Highly recommend adding this one to your shelf—you won’t be able to put it down.

The Book of Lost Hours is a beautifully imagined, atmospheric novel that weaves together history, memory, and time travel in a way that feels both intimate and sweeping. The concept of a timeless library holding the memories of those who came before is haunting and captivating, and the dual timelines of Lisavet and Amelia are equally compelling. While a few pacing issues kept this from being a full five stars for me, the book’s emotional depth and originality made it a standout read. Perfect for fans of The Midnight Library and The Ministry of Time, this is a story about the power of memory and the courage it takes to rewrite history.

Absolutely fantastic book. Will be giving it five stars and recommending it to everyone on my book group on Facebook!

Historical fiction mixed with time travel and magic. Loved it. I’m rarely surprised by twists but this one got me. One of the better books of the year so far.

Historical fiction is not normally my thing but I was happy I took a chance. From the characterization to the settings and the rules of the universe.

Thank you to #NetGalley for an ARC of this novel. If you are a fan of mystical realism and historical fiction this book is for you!

The first character in the novel is Lizavet, her father is a clock maker and also the creator of watches that allow one to enter a library suspended outside of time where the worlds memories are saved. Lisavet ends up locked in here without a watch during Kristalnacht, her father is killed before he can come back for her. She comes of age in this space and sees all that happens here.

There is also Amelia and Moira's story set in 1965, Amelia is grieving the loss of her uncle and Moira is a coworker from a branch of the CIA. Moira becomes the caregiver for Amelia as she has no other family besides her uncle. Moira has many secrets and information she slowly shares with Amelia. All the characters in this novel are distrustful, there are layers of conspiracy, censorship and many opinions on what memories from the world should be allowed to remain in the collective memory library.

It's hard to explain this book without giving too much away. If you are not a fan of sci Fi and stretching reality then I think it would be hard to get into this book. That being said, I am not a huge fan of this type of genre, however this story has notes of censorship and themes that are relevant to our own world history of the victors writing history and the dominant cultures silencing of other voices. There is also elements of coming of age and romance so even if you start getting lost in time theory you get brought back to the familiar love stories and growing pains that repeat no matter the time.

The Book of Lost Hours by Hayley Gelfuso is a mind bending page turner about time, memory, and fate.

In 1938 Germany, Lisavet Levy is the young daughter of a watchmaker with mysterious powers. In order to save her from the Nazi's he pushes her through a magical door conjured by his wristwatch where she becomes lost in time- a library that stores personal and collective memories. In this beguiling place, Lisavet grows up and attracts the attention of a network of spies whose aim is to manipulate time for their own nefarious purposes.

I have read many time-traveling books over the years, and The Book of Lost Hours is the best story I have read. Part mystery, part thriller, with just the right amount of magic, this book pulled me into its beguiling world of espionage and fantasy. Lisavet was an extraordinary character whose transformation was heartbreaking, although one of the best character arcs I have read in a long time. The twists and turns and reveals in this story mirrored the paradoxical nature of time that was explored in a captivating metaphysical way. The notion that time can be manipulated really speaks to the revisionism we see happening in our world, and the sci-fi deep dives into physics and consciousness wove perfectly into the big questions asked in this story about the nature of reality. The book gave vintage science fiction vibes and 1960s spy thriller aesthetics which is making a comeback right now. I couldn't help but think that the magical time space in this story could be the origin story of the library in The Midnight Library by Matt Haig.

I really loved this story and its complex plot and explorations of time- what happens if we change the past? What if there are parallel versions of our lives out there somewhere? Where is the collective consciousness actually stored?

The Book of Lost Hours by Hayley Gelfuso is the perfect read for fans of The Midnight Library and The Adjustment Bureau.

Describing this book as “for lovers of The Midnight Library” really was genius - I loved that one and I loved this one! As far as historical fiction novels go this one had less details about the specific timeframe and more details about the plot when compared to others I’ve read. This story was focused on other aspects with the setting kind of taking a lesser role. I really enjoyed the characters! The main ones were really relatable, and I loathed the antagonist the whole time. I enjoy when a book makes me feel things. The pacing was good. I felt it was slightly slow to start but with the amount of story in this one it came along nicely. I thoroughly enjoyed the author’s writing style - half the time I was in awe at the pretty language and the other half I was wondering how the author would conclude the story. I was also shocked at several plot revelations which kept me engaged with the story. Overall I really loved this book!

My thanks to Netgalley and Atria Books for providing a free e-copy of this book in exchange for an honest review.
Time travel, the whims of history and love; three messy, complex ideas that would be a challenge to approach alone. Hayley Gelfuso pulls off a remarkable debut by weaving them together into a story that speaks to what it means to be human and find resistance in overwhelming times. Plus, it has good ol’ fashioned pining to keep things interesting.

Without dimming the novel’s voice by way of comparison, the Book of Lost Hours is reminiscent of The Ministry of Time, The Bone Clocks and, surprisingly, The Book Thief. The novel is a story about stories, the importance of memory and the necessary resistance against the co-opting of history while acknowledging the fluidity of an agreed-upon historical canon. If this scattered description of influences and ideas sounds a tad unwieldy and convoluted, then it accurately captures the novel, yet not to the narrative’s detriment. Instead, the maelstrom of ideas and questions swirl around an essential, human love story at the centre, about a boy and a girl, their beliefs, and the world they want to leave behind.
Lisavet Levy is one of two heroines, originally from 1938 but slipping into the liminal timestream at the outset of the story. Amelia Duquesne is her counterpart in 1965 and is slowly unravelling the secret life of her uncle Ernest and his ties to the Temporal Reconnaissance Program with help from the agency’s director, Moira. While the book is plenty plotty, it soars because of the characters. I’m relatively green to historical sci-fi romance — is there an agreed-upon portmanteau like romantasy to make that description a bit less unwieldy — but I found the characters played enough outside of the established tropes to pay respect to the reader’s expectations without losing any sense of originality in the cliches. Gelfuso crafts a layered and complicated cast who are understandable in their motivations without being absolved of their faults or failings. As the novel deals with the world of covert agencies and undercover operators, to give away any more of the characters would take away part of the fun of reading and enjoyment of spending time with the cast. Except for Jack, he encapsulates the repugnancy of a power-hungry bureaucracy.
Again, for fear of spoilers, the less directly on the plot, the better. Gelfuso balances the trappings of a spy novel with the time-spanning historical romance. I was surprised to learn this was her debut, as there was a confidence to the pacing and timeline-hopping between the two protagonists. As this was pitched to me as a romance, there are some familiar turns and beats touched upon, but it would almost be insulting if certain expectations weren’t met.
Even if they’re contained within this one novel, which is surely not the case, these ideas and beliefs matter. The urge to placidly allow the greater forces of powerful men, corporations and governments to steamroll over the world and the progress we have made in an attempt to reshape it into a twisted reflection of their own image on its face seems easier. Doomscrolling through the news or tuning it out entirely feels like the best option when the world feels like it is burning around you, but it's during these times that I find myself seeking out stories of hope and resistance. I’ll fail to describe how the themes of The Book of Lost Hours resonated with me, and there might be a time in twenty years when I revisit it to find that the novel is needlessly optimistic when I’m living in a better world, but for the moment, the story was a balm without ever falling into saccharine complacency.

An interesting read I loved all of the magical aspects. It was all of the things a good book needs; fast-paced, well-written, and hard to put down!

From pre-WWII Germany to the Cold War-era America, The Book of Lost Hours is a love story of a woman who grew up in the time space, a library filled with books containing the memories of all who bore witness to history.

The story had some touching moments that gave me goosebumps! This felt like a Romance sci-fi fantasy, which isn’t my cup of tea (I should’ve considered the genres more carefully). The first half was really heavy on romance, more than I’m used to. The middle was page-turning—the different timelines were done well—very nice! But I couldn’t understand the sci-fi/time aspects so using watches and going inside the memory/books felt more like a magical portal fantasy. This Romance book was not for me after all, but it was overall okay. For fans of The Book of Doors and Romance. Thanks to Atria Books for the opportunity to read an ARC of this novel.

I kept coming back for more of this clever, beautiful, genrebending book. The author seamlessly blends romance, sci-fi, historical fiction, and suspense to create a beautiful story with well-developed characters. The breadcrumbs and foreshadowing were very well done, and kept me reading to see how things would unfold.
In my opinion this book did not suffer from the common historical fiction issue of jumping back and forth between timelines and being hard to keep track of. She had a tendency to stick with a certain storyline for a while, and then make it obvious that the focus was shifting.
This book blew me away. I'm excited for the opportunity to recommend it to library patrons!

♡Thank you to Netgalley and Atria Books for giving me this ARC in exchange for an honest review♡
Rating: ★★★★☆ (4/5)

The Book of Lost Hours is a contemplative and poignant novel that beautifully addresses the themes of memory, loss, and self-discovery. Hayley Gelfuso's debut novel (!!!) is a tear-jerking reminder that the journey of self-discovery is typically in the quiet, fleeting moments of existence. Those readers who appreciate literary fiction with psychological acumen and compassionate, multi-dimensional storytelling will definitely find a rewarding read in this novel.
Highly recommended for readers who enjoy character-driven stories with rich emotional layers and a reflective narrative.

A story about time, both physical and metaphorical, as well as a love story that defies all boundaries.

On the night of Kristallnact (1938) Lisavet Levy is hidden by her father inside the Time Space, a mysterious untethered library that contains all of the past's memories stored in books. When he does not return for her, Lisavet grows up in this liminal space, learning to walk through humanity's memories, both big and small. When Lisavet discovers that government employees called timekeepers are entering the Time Space to destroy memories and preserve their country's preferred depictions of the past, she makes it her mission to reverse and thwart these decisions. Her life forever changes again when she meets an American timekeeper named Ernest Duquesne.

This was a lovely historical time-travel romance, replete with mediations on censorship and bigger picture ideas about who writes/remembers history. I appreciated the intertwining of these larger and particularly apt discussions (particularly in our current climate) within the more traditional story base.

The story was well-paced, and moved relatively quickly. Gelfuso's writing was lyrical and poetic, evoking the dreaminess of a library made of memories (although, aren't all libraries such). Without diving too deeply into the plot, to avoid spoilers, stakes were high and as the book progressed, things complicated nicely. Although I guessed many of the twists, they culminated in a satisfying way.

I appreciated that Lisavet was a multi-faceted character, with real flaws- it added a layer of authenticity to the story. I sometimes felt that Eugene was written to be the "perfect man", and this stylistic difference between the two characters could be a bit jarring. That being said, their relationship was a high point of the book, and I enjoyed their scenes together immensely.

The story was quite cinematic, and I believe would be easily adaptable to another medium. Overall, this was a lovely book that should have wide appeal.

Thank you to Netgalley for giving me this ARC in exchange for an honest review

⭐️ - 1 star
Dnf at 45%

So I usually write long detailed reviews…but this book isn’t worth any more of my time. The entire plot was so unrealistic and lacked the magical spark that would’ve kept me interested. I was just so bored through the whole thing, finding myself literally praying the chapter was almost over. On top of that, the writing style was just super dry and I mentally couldn’t get through it.

To be fair, I’m not a fan of time travel romance to begin with and thought that this might change my mind, but I was so wrong. I think I’m ok never picking up a time travel romance again, I’ve had my fill with this. I respect the author for putting so much time and worldbuilding into her book, but it just wasn’t for me.

The concept behind this book was what drew me in. It’s unique and audacious. I’m a big fan of works that deal with memory and have some fantastical elements. And ones set (partially) in the Cold War? With time travel? And espionage? I’m in. Its execution was a bit confusing at times, both in terms of the central mechanics behind the timekeepers and the ending. The main character seemed out-of-time, not particularly tied to the reality of her timelines, which detracted from some of the historical elements. Thus, when the author tried to weave in some broader commentaries on themes like racism, or government corruption, or historical narratives, it felt a bit flat. It skewed toward a romance story more than a sci-fi or historical novel, which wasn’t my personal preference. The use of alternating timelines were interesting and the links between the characters’ stories were well-done. It was emotional at times but overall a cathartic read. I found myself enjoying the first part of the book most, losing some steam near the end and leaving me with questions. The chapters varied in length, especially near the middle, chasing the cadence of the read. The twists were somewhat predictable but that didn’t really detract from the reading experience. Overall, this was a solid read with lyrical writing, especially in a debut novel. Suitable for romance-focused readers and fans of The Book of Doors, The Invisible Life of Addie LaRue, and The Midnight Library.

Thank you to NetGalley and Atria Books for the ARC in exchange for my honest review.