An American half-dollar. A beaded crucifix. Tooth roots shaped like a tiny pair of pants. A padlock. Scads of peanut kernels and scores of safety pins. A metallic letter Z. A toy goat and tin steering wheel. A Perfect Attendance Pin.

One of the most popular attractions in Philadelphia's world-famous Mütter Museum is the Chevalier Jackson Foreign Body Collection: a beguiling set of drawers filled with thousands of items that had been swallowed or inhaled, then extracted nonsurgically by a pioneering laryngologist using rigid instruments of his own design. How do people's mouths, lungs, and stomachs end up filled with inedible things, and what do they become once arranged in Jackson's aura-laden cabinet? What drove Dr. Chevalier Jackson's peculiar obsession not only with removing foreign bodies from people’s upper torsos but also with saving and cataloging the items that he retrieved?

Animating the space between interest and terror, curiosity and dread, award-winning author Mary Cappello explores what seems beyond understanding: the physiology of the human swallow, and the poignant and baffling psychology that compels people to ingest non-nutritive things. On a quest to restore the narratives that haunt Jackson’s uncanny collection, she discovers that all things are secretly edible. Combining original research with a sympathetic and evocative sensibility, Cappello uncovers a history of racism and violence, of forced ingestion and "hysteria," of class and poverty that left children to bank their family’s last quarters in their mouths. Here, the seemingly disparate but equally marvelous worlds of the circus and the medical amphitheater meet in characters ranging from sword swallowers and women who lunched on hardware to the sensitive, bullied boy who grew up to be the father of endoscopy.