A top undercover cop finds and arrests a series of purse snatchers until he discovers an American at the top of an evil ring of thieves.

Returning from Switzerland to Rome, the boss prof. Salviati, called 'The Prince', finds his business compromised by Rudy, a small local bandit full of presumption, audacity and men ready to kill. Commissioner Baldi a young and brave employee, will fight against them with the help of an ex-employee Rampelli.

Hercules searches for the Seven Thunderbolts of Zeus, which have been stolen by renegade gods.