During the Heiji Rebellion in 1159, the samurai Morito desires the lady-in-waiting Kesa, but she is married to Wataru. Morito decides to get rid of his rival. He makes Kesa explain to him how he can kill her husband while he sleeps. Kesa provides very precise instructions, yet when Morito follows through on her plan it is Kesa who gets killed. Morito understands that Kesa has sacrificed herself because she was determined to save Wataru's life and her honour.