Once Antiope has reached the proper age, Cadmos plans to have her ordained as a priestess in his service, to have her shut away from the world of men in a life of enforced chastity.

He turns to the Titans, still incarcerated in the pits of Tartarus, and offers them release if their youngest and weakest, but smartest of their number, Crios, agrees to cast Cadmos into the underworld.

Instantly recognizing his opportunity, Crios begins to criticize the king loudly, starting a merry chase through the city streets before he allows himself to be captured.

As a result, Crios wins and becomes Cadmos' servant, but his uncautious demonstration of his wits and clandestine visits to Antiope eventually alert Ermione to his true intentions.

With the most welcome assistance of his brothers, and some of Zeus' thunderbolts purchased from his cyclopedian weaponsmiths, Crios infiltrates the city, attacks its garrison of soldiers, and eventually stirs its oppressed people into rebellion against their tyrant ruler.

Crios uses one of the thunderbolts to breach an underwater reservoir, sweeping the vapors away and stripping the priests of their advantage, but the waters also begin to flood Antiope's cell, threatening to drown her.

[1] Guliano Gemma's love scenes with Jacqueline Sassard have been considered among the most convincing of this genre and the film as a whole has been called "a masterpiece of Italian cinema".