Maribel, a young typist, goes to work in a construction company as secretary of the director, Don Ignacio. To seduce the girl, he gets a loan so that the parents can buy a new home and that way he gets Maribel to accompany him to London. They start an affair in London. Upon their return to Madrid, both continue their relationship until Carlos appears, a young journalist whom she knows when he interviews the builder. They go out together and the boy falls in love with her. Meanwhile, Maribel is unable to bear the double relationship, talks to both willing to do anything.