Caligula's Hot Nights (1977)

In augusta, Rome of the Caesars the emperor Caligula has a serious problem: it must show your manhood "coram populo" on the occasion of the feast of Priapus. But the Imperial young man is powerless and threatens a fool in front of the people who have come in droves. To defend their dignity will not have to undergo in the care of professor Barnardus in whose clinic goes to flee. Despite being chased by a myriad of inefficient conspirators, the distinguished clinician manages to save the honor of Caligula and happiness of immortal Rome.