When the noxious artefact known as the Wormstone is discovered, only one being in the insidious skaven Under-Empire is vicious and ruthless enough to dare harness its awful power: Grey Seer Thanquol. But when the artefact is stolen by smugglers, Thanquol must recover it. Not only that but a mysterious wizard and his band of henchmen are also trying to stop him. Only by finding the Wormstone, avoiding the murderous attentions of his treacherous subordinates and dodging the displeasure of his superiors in Skavenblight will Thanquol realise his plan to bring the kingdoms of both man and ratkin to their knees...