As the Despoiler's hordes sweep from the Eye of Terror, intent on the destruction of the Emperor's realm, the Space Wolves answer the Imperium's call to battle. Leading the warriors of Fenris into battle on a feral world, Wolf Priest Thokar finds that the enemy are already under attack' from other Space Wolves. But with all of his forces accounted for, who could these mysterious allies be, and how are they related to the Sons of Russ? Read it because It’s good old-fashioned Space Wolves action… and there might just be Space Wolves on both sides. What’s going on? There’s only one way to find out.