Engineer Okuyama's face was disfigured by an explosion in an industrial accident, and he now wears bandages to cover the burns. Feeling isolated and physically rejected by his wife, he consults a psychiatrist. Seeing the frustration Okuyama experiences from his facial disfiguration, the psychiatrist proposes the creation of an experimental
prosthetic mask for him, apparently with great reluctance. The psychiatrist and Okuyama offer a man 10,000
yen to serve as the model for the mask, and the mask is built and fitted onto Okuyama's face. The psychiatrist demands that Okuyama regularly report his sensations and thoughts to him, and cautions Okuyama that the mask may change his behavior and personality so much that he will cease to be the same person. Okuyama tells no one that he has received the mask, and simply lives as a new man, telling his wife that he is traveling on business while he rents an apartment nearby. He tests the mask's effectiveness on a secretary at his company, who doesn't recognize him, and the apartment superintendent's mentally challenged daughter, who does. During a meeting between Okuyama and the psychiatrist, the latter realizes that his patient has already changed, and imagines a world where the mask goes into mass production, subsequently eliminating all sense of morality. Okuyama decides to seduce his wife using his new identity. When she goes along with it too easily, he becomes enraged and reveals himself to her. She in turn says she had known his true identity from the first moment he approached her. He tries to persuade her to give their relationship another chance, but she rejects him, saying she cannot forgive his attempt to deceive her by pretending the mask was his real face. Later, Okuyama attempts to rape a woman on the street, claiming to be nobody when arrested. He is freed thanks to his psychiatrist (whose business card the police found in Okuyama's pocket), who testifies that Okuyama is his patient and that he is not violent. While walking the streets together that night, they see that everyone else on the street is wearing a mask. The psychiatrist asks Okuyama for the mask back, but then changes his mind and decides to let him keep it, as he is a free man. While shaking hands in farewell, Okuyama stabs him to death. Interwoven throughout the film is a separate tale (present in Abe's original novel in the form of a movie the protagonist watches at a cinema and then recounts) of a young woman whose otherwise beautiful face is severely disfigured on the right cheek and neck. She works in a psychiatric ward, whose inmates include many World War II veterans, and lives with her brother. The imagery of these sequences, her repeated worry about the coming of another war, and her asking her brother if he still remembers the sea at Nagasaki (presumably from their childhood there), all suggest that her scars are a result of the
atomic bombing of that city. Like Okuyama, she feels isolated because of her disfigurement. On a trip to a seaside inn with her brother, she makes a romantic overture towards him, to which he is receptive. The next morning, she dresses all in white, removes her shoes, and walks into the ocean, likely intending to commit suicide. Seeing her from the inn window, her brother cries out in despair. == Cast ==