Enigmatic detective Hermes Diaktoros visits a remote island which is home to an ancient icon famed for its miraculous powers. But something about the Virgin troubles him, and Hermes calls on an old friend to confirm his suspicions that the icon is a fake. Ready to hand the matter over to the authorities, Hermes intends to leave – until the island's icon painter is found dead at sea. But has the painter died of natural causes or by a wrathful hand? What secret is a dishonest gypsy keeping? And what haunts the ancient catacombs beneath the bishop's house?