The fascinating untold story of one scientist’s pursuit of a legendary surfer in his quest to define human nature, for fans of Why Fish Don’t Exist and Lost City of Z.

Deep in the archives of the American Museum of Natural History in New York sits a wardrobe of heads—some fifty plaster casts of human faces a century old. How they came to be is the story of one of the most consequential, and yet least-known, encounters in the history of science.

In 1919, the museum’s then-director Henry Fairfield Osborn traveled to Hawaii for a surfing lesson. His teacher was Duke Kahanamoku, a famous surf-rider and budding movie star. For Osborn, a fervent eugenicist, Kahanamoku was a maddening paradox: physically “perfect,” and yet belonging to a notionally “imperfect” race.

Upon his return to New York, Osborn’s fixation grew. He dispatched young scientist Louis Sullivan to Honolulu with an odd task—to measure, photograph, and cast in plaster the Hawaiian people, Kahanamoku in particular. This outlandish assignment touched off a series of events that forever changed how we think about race, culture, science, and the essence of humanity.

In Capturing Kahanamoku, historian Michael Rossi draws on archival research and firsthand interviews to weave together a truly fascinating narrative—at once an absorbing account of obsession, a cautionary tale about the subjectivity of science and the afterlives of eugenics, a meditation on humanity, and the story of a man whose personhood shunned classification.