Tallinn 1419. What links the Keeper of the Quad Dack Tower, a prostitute and a Flemish painter to a haunted house on Rataskaevu Street? All three claim to have seen a ghost near the house, and each of the three is found dead soon afterwards. In the aftermath of these seemingly supernatural events, Melchior Wakenstede, apothecary and assistant bailiff, is charged with unearthing the truth, and when he finds a number of castrated corpses at the house-which had been the scene of some violent murders decades earlier-he begins to research the history of those events and attempts to find out whether, as some townspeople believe, ghosts really can reap their revenge upon the living. When a powerful and very pious old merchant dies, Melchior perceives a connection between this and the other deaths. In his attempts to solve the riddle, Melchior becomes embroiled in the conflicts and rivalries between the religious orders, the merchants´ guilds and the Teutonic Knights as they vie with one another for control of the town. He finds himself in a convent, a brothel, in the company of a clan of wizards and eventually comes up against the Ghost of Rataskaevu Street itself, and, as the threads begin to unravel, what he discovers is more incredible and more terrible than any legend.