The Key (1971 film)

The Key is a 1971 Japanese drama film directed by Toshiharu Ikeda. It is based on the 1956 novel Kagi (鍵, "The Key") by Jun'ichirō Tanizaki. The film explores themes of marital sexuality, obsession, and voyeurism through the story of an aging professor who tries to reignite passion in his marriage by secretly documenting his wife's reactions to various stimuli.

The film differs from other adaptations of Tanizaki's novel by taking a more explicit and visually daring approach to its subject matter, a characteristic which contributed to its notoriety. The story revolves around a middle-aged professor and his much younger wife, Ikuko, who are experiencing a decline in their marital intimacy. Desperate to recapture their initial passion, the professor employs increasingly provocative methods, including photography and manipulation, designed to arouse both himself and his wife, sometimes at the expense of her well-being. He often relies on his daughter's fiancé, Kimura, to instigate jealousy and further complicate the dynamic. The intricate relationships and psychological games play out against a backdrop of traditional Japanese customs and societal expectations.