Altered states of consciousness (ASCs)--including dreams, hypnosis, spirit possession and brainwashing--have long captivated contemporary culture. In the 20th century, Hollywood integrated ASCs into an array of films, reflecting society's fascination with the subject. After early cinematic portrayals laid the groundwork, the depiction of ASCs on the silver screen surged with the advent of special effects in the 1960s and are abundant in the present day. This book traces the rise and proliferation of ASCs within American cinema, focusing on major studio releases from the 1940s onward. By examining various aspects of altered consciousness, from weaponized hypnosis to spiritual encounters, the text sheds light on the cultural reception of these films, recent research on ASCs and discrepancies between scientific knowledge and cinematic representation.