When Peter the Shifter decides to seek out his mother, Mavin Manyshaped, he doesn't realise that he will end up on an adventure that will solve one of the great mysteries of his time. His friends Windlow the Seer and Himaggery the Wizard have disappeared, as have many Gamesmen who believe in justice and do not Game with people's lives.

Peter has heard that the Gamespieces that are used in SChooltowns are made by magicians in the north, and that is where he must go to find Mavin. After making his way through Schlaizy Noithn, the land of the Shifters, he finds Mavin watching an area known as the Blot. There are magicians here, and everyone avoids it, everyone except Gifters, people who work ill with travellers and play covert Games.

Mavin and Peter must enter the Blot, and discover it's mysteries, to find their friends and end an old evil. What they find there changes everything they know about themselves, the Great Game, and their entire world.