The play begins with Mother conversing with her daughter, Martha. The two are talking about a guest who has just arrived in their lodgings. Mother, Martha, and Old Man have been hosting rich lodgers and kill them to steal their money. Martha is always sad something which disturbs her mother. Carried by the greed of money, Martha kills lodgers to live by the sea. Mother and Maria don’t know the present guest is Jan. Jan is Mother’s son and Martha’s sister. When he arrives home, nobody recognizes him. Jan is accompanied by his wife, Maria. Jan left home twenty years ago and his sister was a little girl. Maria wonders how Jan’s family doesn’t recognize him.
When registering to have a room, Jan lies about his name and place of birth. Mother seems to enjoy the conversation between Jan and herself, but Martha is not buying into their stories. Lastly, Mother and Martha excuse themselves and leaves Jan in the room. Mother is against the killing of this new guest. However, Martha insists on killing the last victim. Martha brings a poisoned tea as usual. Jan complains that he has not ordered the tea. But, Martha calms him by saying it was a misunderstanding of the Old Man.
Mother comes to the room to discourage Jan from taking it. By the time she enters the room, Jan had already taken the tea. Jan falls asleep and he is drowned in the river. The following day Mother feels tired, but Jane is happy. The two realize that they have killed their kin. Mother kills herself. Maria comes asking for her husband and Martha tells her everything before killing herself too. Ultimately, Maria starts crying for help but no one can help her.
