Lina and her ailing father have taken refuge at an enclave called the Sea, a staging post between migrations, with only a few possessions, among them three volumes from The Great Lives of Voyagers encyclopaedia series.

In this mysterious and shape-shifting building, pasts and futures collide. Lina befriends her unusual neighbours: Bento, a Jewish scholar in seventeenth-century Amsterdam; Blucher, a philosopher in 1930s Germany fleeing Nazi persecution; and Jupiter, a poet of Tang Dynasty China, and through their stories, she comes to understand the role of fate in history and the way that ideas can shape the world, and to face up to the cost wrought on her family and others by her father's betrayals.