The monks of Glastonbury have discovered two strange skeletons buried in their graveyard - one is tall, the other small and delicate. Are these the remains of King Arthur and Guinevere? King Henry II, on hearing of the discovery, demands evidence that the legendary Arthur is dead in order to stop his belligerent Welsh subjects believing that their Once and Future King will return to lead them against him. And it is his Mistress of the Art of Death, Adelia Aguilar, who he calls upon to examine the bones. But someone doesn't want the skeletons identified - and is prepared to kill in order to prevent it.