Colonel-Commissar Ibram Gaunt spent a year fighting as part of the underground resistance on the enemy-held world of Gereon. When he left, he promised that he would bring the forces of the Imperium to liberate Gereon’s citizens from their oppressors. Now he has returned, a crusade army at his back, but he finds a world devastated by war and a people irrevocably damaged by the taint of Chaos. Now Gaunt must fight to save Gereon not only from the enemy, but from the Imperium itself.