Marcus Sinclair is a history teacher whose life is stuck in neutral when he inherits a papyrus scroll from his antiquarian uncle. The mysterious scroll might contain a lost masterpiece from ancient Rome or perhaps an ancient recipe for personal tranquility, but it's unreadable unless Marcus can figure out a way to unroll the scroll without destroying it. His quest takes him to Naples, where he befriends a Google software engineer days before the man is found dead. Marcus is interviewed by an investigative journalist, Kristi Grainger, and they find themselves on parallel paths leading to a Neapolitan trafficker in antiquities, a tech mogul obsessed with the distant past, and a clutch of academics searching for the lost library of Herculaneum. In a seaside city that is by turns lush and lethal, Marcus must confront the unraveling of more than a scroll.

This novel is inspired by a real place — the Villa dei Papri, the only library from antiquity to have survived — and coincides with the Vesuvius Challenge, a real-life international competition to decipher Herculaneum scrolls.