An attractive woman, Masuko, discovers her lover is currently married. And even though she had certain suspicions, the thought of possibly breaking up a marriage wears heavily upon her conscience. For his part, lover boy is not at all happy in his marriage and wants a divorce. The problem is that his wife is emotionally unstable and the thought of a divorce is more than she can handle. Matters become even more complicated when cheated-on wife allows her niece to move in with them and she becomes immediately attracted to cheating husband, too.