Roland and his tet have just returned to the path of the Beam when they discover that they are being followed by a group of inexperienced trackers. The trackers are from the town of Calla Bryn Sturgis, and they desperately need the help of gunslingers. Once every generation, a band of masked riders known as the Wolves gallop out of the dark land of Thunderclap to steal one half of all the twins born in the Callas.