A holiday at the seaside. After a wild night out, Dr. Rosta and his friend Petr philosophise about the essence of human nature. Their heated debate about whether humans are gods or devils is interrupted by the arrival of a naked man from the nearby Paradiso nudist beach. Soon enough, however, we discover that this never really happened and that the doctor is also the director of a somewhat experimental documentary. The idea behind the movie is to analyse how a naked person differs from an ape. The 'material' for this investigation are willing nudists attracted by money, curiosity and exhibitionism. The project is being financed by a nouveau-riche Russian producer named Igor. He naively believes that he can push the filmmakers' philosophical concerns aside and rake in on a titillating comedy about nudists. The situation at Paradiso beach is heading irrevocably toward a dramatic climax.