 In Santiago, Chile, the schoolteacher Luisa proposes a debate about sex with the parents of her students with the intention of giving classes about sex education to the youngsters. Luisa is a young independent woman that is split between the love for her also young mate, the painter Valentín (Francisco Pérez-Bannen), and for her experienced lover, the middle-age father of one of her students and successful writer Jorge. Jorge still lives with his wife Mónica, but their marriage ended and they do not even talk to each other, but his affair with Luisa is limited to sex. In the meeting, the parents are divided in groups, and Luisa stays with Jorge, and the couples Álvaro and his pregnant wife Elena and the butcher Emilio and his frigid wife Maca. Álvaro is a wolf man, harasses all the beautiful women that he meets for one night stand, unfaithful and neglecting his wife at home. When Luisa finds that she is pregnant and Valentin is going to work in São Paulo, she makes a decision with her sentimental life. When Elena meets her former friend from university Carlos Rojas, Álvaro becomes jealous and tries to commit with Elena. When the liberated and independent niece Susan spends a couple of days in his home, the faithful Emilio is seduced by the sexy and gorgeous young woman, while Maca finds her sexuality, reading magazines and going to the gynecologist.