Samuel Pipps, the world's greatest detective, is chained in the belly of a ship bound for Amsterdam in 1634, accused of a crime that will see him hanged upon arrival. His bodyguard Arent Hayes watches helplessly as their vessel, the Saardam, prepares to depart Batavia with a cargo of precious spices, a company of Dutch East India merchants, and a demon that may or may not be stalking the decks—a creature promised by a leper's curse moments before the ship set sail. What follows is a locked-room mystery stretched across eight weeks of open ocean, where every passenger becomes a suspect and every shadow might conceal something worse than human malice. Turton constructs a baroque puzzle box of a novel, layering supernatural dread atop the rigid hierarchies and simmering resentments of colonial trade, all while the ship itself seems to conspire against its inhabitants through fire, murder, and inexplicable omens that suggest either demonic intervention or an exceptionally clever killer. The brilliance lies in how Turton sustains the ambiguity between rational deduction and genuine horror, refusing to let the reader settle into either genre's comfortable rhythms. With Pipps imprisoned and unable to investigate, the detection falls to unlikely hands, and the novel becomes as much about who gets to solve mysteries—and why—as it is about the solution itself. Historical detail and impossible crime merge into something that feels both meticulously researched and deliriously inventive.