A medical student named Hirosuke Hitomi escapes from a mental institution and assumes the identity of a recently deceased nobleman who looks strikingly similar to him. Hirosuke's quest for his true identity leads him to a desolate island inhabited by malformed men, ruled by a mysterious and grotesque figure, Jogoro Komoda, who performs bizarre and sadistic experiments on the island's other inhabitants. With mounting confusion and horror, Hirosuke delves deeper into the dark secrets of the island, uncovering a web of family betrayal, madness, and grotesque body modification experiments.

As Hirosuke’s exploration continues, he meets various eccentric and tortured characters who each hold pieces of the puzzle that explain the island's macabre reality. He uncovers terrifying truths about his lineage and the true purpose of Jogoro's twisted vision. The unearthing of these haunting secrets steers him toward a climactic revelation that forces him to confront his own identity and the sinister legacy of the Komoda family. The island becomes a nightmarish crucible where past and present horrors intertwine, leading to a spine-chilling resolution as the truth is finally laid bare.