The Manitou is a 1978 American supernatural body horror film produced and directed by William Girdler, and starring Tony Curtis, Michael Ansara, and Susan Strasberg. It follows a woman in San Francisco who begins developing a fast-growing tumor on the back of her neck which is discovered to be supernatural in origin. It is based on the 1976 novel of the same name by Graham Masterton, which was inspired by the concept of manitou in Native American theology, believed to be a spiritual and fundamental life force by members of the Algonquian peoples. The film was Girdler's final feature, as he died in a helicopter accident prior to its release.