Eduardo, a typical bourgeois man from Mexico City, goes on a business trip to a province, accompanied by his lover. While there, he picks up a large sum of money and, after a spat with his lover, sets off on his drive back to the city alone. On the way, his car gets stuck in the mud and he's helped by four campesinos who ask him for a ride to the city in return. The trip proves extremely tense for Eduardo, who's increasingly gripped by paranoid fears that the men intend to rob and murder him.