Rome the beautiful is dying. A strange meeting is held by nine families who share the Roman Empire. To retain their power, they decide to back a new religion - Christianity - and its representative, the Pope. Who are these nine mysterious families? Much later, during the Renaissance, a brigand called the Scorpion makes a living by unearthing relics from the Roman catacombs, which he sells on to princes and bishops. Trebaldi, a powerful cardinal, takes an interest in this Scorpion, who is either a creature of the devil or a witness to a cursed era.
