The Relentless Dead - Steve Lyons

Five hundred years ago, Oleris III was ravaged by a Chaos plague. Now it is a world of tombs and catacombs. It belongs to the dead. Colonel Graven and his 401st Krieg Regiment are charged with searching for a missing inquisitor in the bone-filled ossuary tunnels beneath the planet. But the dead are stirring, and down in the labyrinthine darkness his kill team comes face to face with unspeakable horrors. As whispering spectres seed fear and suspicion, turning allies into foes, the colonel has ghosts of his own to battle. Haunted by a tragedy of his own making and unable to trust anyone, even the most resolute Death Korpsman might start to doubt himself. But on this world, it could be the death of him.