Lemartes is the Guardian of the Lost, a Space Marine warrior who balances on the edge of madness, ever close to falling into the grip of the Black Rage, the secret curse of the Blood Angels Chapter. When he is awakened to lead the Death Company into battle on the war-wracked world of Phlegethon, Lemartes must battle his incipient madness as his forces clash with equally insane foes: the blood-crazed servants of Chaos.