For fans of The Ministry of Time and The Midnight Library , a sweeping, unforgettable novel following two remarkable women moving between postwar and Cold War-era America and the mysterious time space, a library filled with books containing the memories of those who bore witness to history.

Enter the time space, a soaring library filled with books containing the memories of those have passed and accessed only by specially made watches once passed from father to son—but mostly now in government hands. This is where eleven-year-old Lisavet Levy finds herself trapped in 1938, waiting for her watchmaker father to return for her. When he doesn’t, she grows up among the books and specters, able to see the world only by sifting through the memories of those who came before her. As she realizes that government agents are entering the time space to destroy books and maintain their preferred version of history, she sets about saving these scraps in her own volume of memories. Until the appearance of an American spy named Ernest Duquesne in 1949 offers her a glimpse of the world she left behind, setting her on a course to change history and possibly the time space itself.

In 1965, sixteen-year-old Amelia Duquesne is mourning the disappearance of her uncle Ernest when an enigmatic CIA agent approaches her to enlist her help in tracking down a book of memories her uncle had once sought. But when Amelia visits the time space for the first time, she realizes that the past—and the truth—might not be as linear as she’d like to believe.

The Book of Lost Hours explores time, memory, and what we sacrifice to protect those we love.

I received an advance galley of this book courtesy of the publisher via NetGalley. All thoughts are my own.

Time travel stories and I have a complicated relationship. I love the idea of them, but they don’t always land. Too many confusing mechanics can make me want to tap out. Thankfully, this book was a win. It hooked me with its clever setup and kept me invested with layered characters and an emotional core that made the adventure matter.

The concept is reminiscent of The Midnight Library: we have a soaring library that holds the books of our memories. Each volume captures moments that can be read, stepped into, and even lived again. It’s haunting and imaginative. On one side, you’ve got people burning these memories, determined to prevent history from repeating itself. On the other, rogue preservers fight to protect them, slipping into the past to experience it firsthand and stealing the memory books that others seek to destroy. That tug-of-war between erasure and preservation grounds the story in a moral gray zone I found fascinating. Should some memories be destroyed for the greater good? Or do we risk losing truth when we start rewriting what’s been lived? (Sound familiar U.S. residents?)

At the center of the book is Lisavet, who grows up inside this library of memories after her watchmaker father disappears in Nazi-occupied Germany. Her life is shaped by ghosts, words, and fragments of other people’s lives. She’s both isolated and deeply connected, her identity stitched together by the stories of others. I loved how the novel let her carry that duality. She’s haunted, yet she becomes a protector. Later, Amelia takes the stage, a teenager drawn into the same strange, fragile world through her murdered uncle. Watching the two threads of Lisavet and Amelia’s lives cross was one of the book’s big emotional strengths.

And yes, there’s romance and intrigue woven into the mix, but it never overshadows the heart of the story. It enhances it. Even days after finishing, I found myself thinking about how memory shapes identity, how memories aren’t always reliable and not everyone remembers things in the same way.

The time travel mechanics worked well for me, which is not something I can always say. The rules made sense, and Gelfuso kept them consistent. Nothing pulled me out of the story with “wait, how does that work again?” moments. Instead, the movement through time flowed well. Each leap mattered, and moved the story forward.

If I had one gripe, it’s that the story didn’t surprise me much. I saw the major turns coming. The reveals were satisfying but predictable, and that kept me from giving it a full five-star rating. Still, predictability isn’t always a bad thing. Sometimes the journey is enough, and this was one of those cases. The writing is sharp, the pacing steady, and the characters memorable. Even knowing where things were headed, I enjoyed every step.

Overall, this is a thoughtful and engaging spin on time travel. It balances danger, romance, and family with a strong dose of wonder. If you like your speculative stories anchored in emotion rather than just clever twists, this one deserves a place on your shelf.

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