Renato, the young scion of a rich house must marry and give an heir to the family. However, he does not want to touch his fiancee Giulia before the wedding and but intertwines a relationship with the maid Claretta, while Giulia cheats on him with Dr. Serra, who checks the health conditions of her fiance. Despite the sudden death of Signora Elena, Renato still decides to get married on the fixed date in order to satisfy his mother's wishes. One evening, however, Ernesto, Giulia's brother, after having seduced earlier the maid Elvira tries to do the same with Claretta but she refuses him. Aware of Ernesto's attempt to violence, Renato kills him and runs away. Then he goes to the home of Giulia and kills her with scissors after having forced her to have sex with him. Reached Claretta, the two take refuge in a farmhouse where they had already gone before being joined by a friar who marries them; during an embrace Renato is cut off by a heart attack. Claretta finally discovers that Renato had previously modified his will, making her the heir of his family's estate and she learned from Doctor Serra that she was pregnant carrying the heir wanted by Elena.