Like much of Imamura Shôhei’s work, The Eel deals frankly with matters of sex and sexuality, but with an emotional detachment akin to an anthropological study. That detachment is on display from the start, when businessman Yamashita Takuro (Yakusho Kôji) acts on an anonymous note informing him of his wife’s (Terada Chiho) affair and sneaks home one evening to catch her in the act. In a scene scored only to the faint chirping of insects, Yamashita spies on the lovers with an aloof curiosity before calmly heading off to grab a knife and murder the pair. Only the spray of arterial blood that splatters the camera lens jolts the scene from its reverie.

The film jumps to eight years later as Yamashita leaves prison on parole, toting an eel from the facility’s pond that the warden allowed him to keep as a pet for good behavior. While...