Forty years ago in Laetoli, Tanzania, a team of paleontologists discovered a set of 3.6-million-year-old fossil footprints of early hominids —likely our ancestors. The team was led by Mary Leakey, the pioneering subject of this animated feature. The film covers many highlights of her career and her relationship with her research partner and husband, Louis Leakey. Leakey described the discovery of the Laetoli footprints as one of her most important finds.