Maciste arranges for himself and his new friend Bangor to be captured by a mysterious band of white-clad marauders and taken to an underground city. There the two are forced to turn an enormous wheel along with other captives as part of a gold-and-diamonds mining operation. The underground city's queen, Halis Mosab, takes note of the handsome, muscular Maciste and chooses him to be her consort if he can meet such challenges as saving the kidnapped Princess Saliura from a gigantic ape. Maciste kills the ape and carries Saliura back to the aboveground world. The white-clad marauders can't follow them if it means being caught in the sunlight which instantly dissolves them. Maciste then returns to the underground city to save the other captives. Meanwhile, high priest Kahab informs his son, Katar, that their queen is not one of them but, unbeknownst to her, was kidnapped as a small child from the "world above." If Katar can marry her...

Elio is a member of a group of youngsters, all from good families, who have fun spending their days taking on silly challenges and perpetrating illicit activities. Their actions escalate and lead them to commit a robbery. Unfortunately, the robbery ends badly and a death ensues, leaving the group implicated in a murder. The police are groping in the dark due to the complexity of the investigation. Meanwhile, Elio meets and falls in love with a nightclub stripper, Suzette. The rest of the group, after a while, think they've got away with it, but make a reckless mistake that allows the police to track them down and arrest them.