Cloud Cuckoo Land by Anthony Doerr is an ambitious, multi-layered literary novel that connects five dreamers across different periods of history, united by an ancient Greek story and their shared struggle to find hope in worlds threatened by destruction. Published in 2021, the novel moves between Constantinople in 1453, present-day Idaho, and a distant future aboard an interstellar spacecraft. Its central ancient text tells the story of Aethon, a man who dreams of reaching a mythical utopian paradise, and this story becomes a source of comfort and connection for the novel's characters. 

The historical storyline follows Anna, an orphan living inside Constantinople during its siege, and Omeir, a village boy forced into the invading army. In contemporary Idaho, Zeno, an elderly former prisoner of war, works with children to stage a play based on the ancient story, while Seymour, a troubled teenager, becomes involved in a violent act at the library. In the future, Konstance lives aboard the spacecraft Argos and preserves the same ancient story while humanity searches for a new home.

Through these interwoven narratives, Doerr explores the survival of stories, the importance of libraries, human resilience, environmental stewardship, war, displacement, imagination, and the connections between generations. The novel ultimately presents storytelling and books as forms of survival—ways in which human knowledge, hope, and compassion can endure even when civilizations and environments are threatened. Cloud Cuckoo Land was a National Book Award finalist and became a New York Times bestseller.