Brian Cohen is born in a stable a few doors down from the one in which Jesus is born (a fact which initially confuses the three wise men who come to praise the baby Jesus, as they must put up with Brian's boorish mother Mandy until they realize their mistake). Brian grows up to be an idealistic young man who resents the continuing Roman occupation of Judea, even after learning his father was a Roman Centurion -- Naughtius Maximus (who may indeed have raped Brian's Mother initially, with her claiming 'well, at first, yes'). While attending Jesus' Sermon on the Mount, he becomes infatuated with the attractive young female rebel, Judith. His desire for Judith and hatred for the Romans lead him to join the People's Front of Judea, one of many factious and bickering separatist movements, who spend more time fighting each other than the Romans. The group's cynical leader Reg gives Brian his first assignment as a rebel: an attempt at scrawling some graffiti ('Romanes eunt domus', poorly translated Latin for 'Romans Go Home') on the wall of the governor's palace. This succeeds beyond his wildest expectations when he is caught by a passing Roman guard who, in disgust at Brian's faulty Latin grammar, forces him to write out the 'corrected' message ('Romani ite domum') one hundred times. The walls of the fortress are literally covered by dawn.
When the Roman guards change shifts at daybreak, the new guards immediately try to arrest Brian. After a series of misadventures, the fugitive winds up accidentally taking the place of one of a motley group of mystics and prophets who harangue the passing crowd in a plaza. Forced to come up with something plausible in order to blend in, he babbles pseudo-religious nonsense which quickly attracts a small but intrigued audience. Once the Romans have left, Brian tries to put the episode behind him, but has unintentionally inspired a movement; after a night