The son of a heinous sinner, Medardus is brought up in a monastery to atone for his father’s wicked ways. However, after succumbing to temptation, Medardus himself is lured into a life of sin. A labyrinthine plot sees him embarking on a fantastical journey into the world, meeting his doppelganger, involving himself in a game of double impersonation, and becoming embroiled in murderous intrigues at the Vatican, before the mysterious curse hanging over him and his family is finally explained.