King Androcles of Thebes commands a ship in search of a threat to Greece, predicted by an atmospheric oracle. Hercules is part of the crew, but the strongman falls overboard in a thick fog. Washed ashore, he saves a young Ismene from Proteus, an evil, shape-shifting creature. Ismene takes Hercules to Atlantis, where he discovers that her mother, Queen Antinea, has captured Androcles. Hercules schemes to rescue him and thwart Antinea's dream of world conquest.

During his military service, the young singer Gianni Traimonti falls in love with Carla, the marshal's daughter.

After the death of his estranged father, professional rainbow-watcher Stefano finds out he has a 13-year-old half-brother, and that he must become his legal guardian to receive the inheritance.

Two youths who work together in a department store love each other but also their supervisor has his eyes on the young girl.

A young singer secretly gets married since he does not want to let his fans down. After a while the gutter press make up a love story which seriously worries his young bride.

Federico, his girlfriend Laura and her cousin, Caterina, are three young people full of hope, united by a great friendship that seems indissoluble. The three work in a department store but, when Caterina decides to attempt a musical career, given her vocal skills, everything changes. Caterina becomes a successful singer and Federico falls in love with her. Caterina, who however does not want to make her cousin Laura suffer, pretends not to reciprocate the young man by making him put his head in order. Meanwhile, the plots of various secondary characters evolve, in particular the fresh marriage between the security guard Antonio and the secretary of the department stores Adelina.

Rita, a vivacious co-ed is in love with her music teacher, a man who leads a double life - bespectacled professor by day and composer of rock songs by night. Will Rita win his heart?

The film tells the difficult love-story between Bobby Tonner, an American singer who came to Naples to meet his old music professor, and the charming daughter of the same professor.