In 16th century Italy, mercenary Marco is hired by cruel duke Astolfo whose unjust reign is threatened by the notorious outlaw the Red Mask.

Italian production of Jack London's well-known, often filmed tale. Gentleman is forced to work in a seal-hunt ship ruled by a tyrannical captain. Violence rules but soon he learns to interact with the captain, just to find a thinking (and ill) man.

Three clumsy thieves come up with a robbery scheme against the "Grandi Magazzini Romani". They call to their aid a skilled "only by reputation" French burglar, Pierre Le Compte.

The evil King Zagro has designs on the beautiful Princess Sira. He wants to marry her so he can take over her kingdom and add it to his own. When Sira is kidnapped, Ursus leaves his farm to rescue her and to eventually lead a revolt against King Zagro.