Marin Cole, a crossword constructor for the London Herald, lands the assignment of a lifetime: cover a clandestine weeklong competition at Wrenfield Manor, a shuttered Gothic estate perched over the cliffs of Dorset. Hosted by reclusive tech magnate Sir Adrian Wren, the 'Vesper Trial' gathers ten savants—codebreakers, magicians, memory champions—each sequestered in a numbered suite and bound by nondisclosure. At first, Marin's stay is intoxicating: the rooms are paneled in rosewood, champagne appears on silver trolleys, and the riddles—clockwork boxes, ciphered sonnets, a chessboard with missing knights—tickle the edges of her old obsession.
But as fog sinks down from the moors and the tide gnaws at the rocks, the puzzles turn mean. In the small hours, Marin watches from a mullioned window as a hooded figure drags a struggling woman across the moonlit lawn toward the folly by the cliff and disappears. The problem? Morning roll call lists every guest present, wrists stamped with Wren's violet crest, voices smooth, smiles fixed. Security swears no one left their rooms. So the manor hums with polite laughter, and the next riddle is unveiled, while Marin canvasses shuttered corridors and locked garden gates, convinced the game has shifted—and someone's playing for blood.
