The great cathedral - the most ambitious building in all Christendom - is rising above the city. Far below its soaring spires, an assassin of unnatural talent fulfils his commission. But there is a witness to the crime: a flamehaired thief known as Jacob the Fox. Pursued by the black-clad spectre, the wily Fox seeks help from a beautiful clothes dyer, her drunken rascal of a father, and her learned uncle, a man of God who loves a battle of wits almost as much as he loves a bottle of wine.