Hirosuke (Teruo Yoshida) a medical student with almost no recollection of the past, is trapped in an asylum, even though being absolutely sane. After being dressed for the murder of a circus girl, also escaping from the loonybin, he spots a deceased man, Genzaburo Komoda, to whom he bears an uncanny resemblance's photo. By pretending to have been resurrected, Hirosuke supposes the dead person's individuality including Komoda's widow along with mistress. Hirosuke recalls memories that convince him to visit the dad of Genzaburo, to a nearby island, home of Jogoro. Whilst on the islandHirosuke not merely discovers Jogoro's plans to build his own'ideal community' (by transforming absolutely ordinary people into dreadful freaks), but in addition the horrible truth behind their own identity.