The plot of Sex and Lucia unfolds with a convoluted mixture of present, past, fantasy and reality. Lucia (Paz Vega) is a beautiful young waitress in Madrid who comes home from work one night and receives news from the police about her boyfriend, a depressed writer named Lorenzo (Tristian Ulloa). She flees to anvisolated island where she lives with a strange, sexy man. The story leaps backward six years to Lorenzo and a strange woman having a sexual encounter on a beach. The child born of this encounter is raised by the woman without Lorenzo. His creativity is lost. He meets Lucia in a restaurant, they fall in love, have a lot of sex and live together. One day Lorenzo learns of his daughter, and meets her and her baby sitter. The movie, now told from Lorenzo’s perspective, is a mix of his dreams with reality.