Scorpion the Vol.2: the Devil in the Vatican, Paperback/Stephen Desberg

The Scorpion, whose mother Trebaldi burnt at the stake for loving a man of the cloth, discovers that his father was the murdered Pope. When Trebaldi addresses a crowd at the end of the mourning period, the Scorpion is there to tell the truth about how the Pope died. Trebaldi claims that the sacred cross of St Peter appeared in his castle.