Catherine Miles is a young student 17 years of age, whom her parents had sent to study in London to perfect the language. At the end of the course, Catherine goes on vacation to the Amazon and her parents organize a boat trip on the occasion of Catherine's 18th birthday, in which Catherine's uncle and aunt also go, but in another boat. During the trip, the boat is apparently attacked by some Indians and Catherine's parents are beheaded. She is taken as a prisoner by a group of Indians, led by the young warrior Umukai.