In the grim darknes of the far future, there is only war... The Fulminata Guard, a Chapter of Space Marines, has been trapped mid-transit in the Warp. Now their ship, the Egreigum, is threatened with being overrun by Daemons from the Warp. Many good Battle brothers fall to the blades of Bloodletters. However, that may end up being the least of their concerns, as the Warp creeps into the minds of some of the greatest Captains of the Chapter, turning them to the ranks of the Chaos Gods...