Birute Galdikas, along with Dian Fossey and Jane Goodall, form the famed trio of “angels” Louis Leakey trained to study great apes in the wild. While Fossey studied the gorilla and Goodall the chimpanzee, Galdikas went to Borneo to study the orangutan and, decades later, emerged as a complicated figure, embroiled in scandal. Spalding’s quest to know this woman takes her from the offices of Galdikas’s foundation in Los Angeles to the Sekonyer River in Borneo, where she discovers a beguiling cast of characters.