In the huge steel factories in Terni (Umbria, Italy), two friends: Mario and Pietro, fight for the love of the same girl, Gina. Pietro dies because of a work accident at the factory. The other workers think Mario is responsible for the death of his friend. Mario, who is innocent, is forced to quit, but his love for Gina and his dedication to his job help him out of his crisis.

Semiramis, a powerful and beautiful Assyrian queen, oversees the construction of the luxurious city of Babylon. She falls in love with Kir, a fallen prince turned into a slave who corresponds to her love. But a palace conspiracy will make the two lovers separate and confront each other.