Tanuma Yuriko is a housewife who lives with her husband Kazuo, their two children and mother-in-law Hatsue. One day, Saori, the wife of Kazuo’s friend Kusumoto Masafumi is strangled to death and Kazuo confesses that he had been having an affair with her. Yuriko suspects that he murdered Saori. Realizing that he cannot get away, Kazuo acknowledges that he killed her and tries to give himself up to the police. However, Yurikodesperately holds him back. She decides to cover up his crime to protect their peaceful family life. Before Yuriko realizes it, a stranger within her starts to take action for the sake of protecting her beloved family. ~~ Based on the same-titled 1966 suspense movie directed by Naruse Mikio.