The story of Brian, a well-meaning Jew from AD 33 mistaken as the Messiah.
Jesus is only a bit-player in this Monty Python comedy, but the rest of the film is meant to reflect on the sort of religion that could 'produce' the messiah we have today.
At the Sermon on the Mount Jesus' words are clearly distorted by distance so that 'Blessed are the peacemakers' becomes 'Blessed are the cheese-makers', suggesting there is a reasonable doubt that any teaching could have survived the ages.
Jesus' reported healing of an 'ex-leper' implies that his celebrated actions might have been viewed completely differently by the people of his day.
Further, Brian's own accidental elevation to messianic status demonstrates that a historical figure is not beyond being manipulated by the political and social forces of his day.
The crucifixion is presented as one of life's hard truths that has to be coped with. If there are any resurrections, they don't happen to your average Brian.