Adapted from the novel by Juan Marse, the film shows two distant worlds in the Spain of the 50's, the suburban and the bourgeois, which are related through two characters, Manolo Reyes, vulgar motorcycle thief who aspires to escape poverty and Teresa Serrat, university student of bourgeois extraction seduced by the revolutionary cause.

A Spanish police chief hires an undercover agent, Eagle, to infiltrate a gang of heroin smugglers. Infiltrating the gang, he uses a female agent as a point of contact. However he discovers that there bigger goings-on than dope. The gang is involved in the transportation of smuggled uranium for the manufacture of nuclear arms for sale to Libya and other aspiring third world countries.