The sons of Sanguinius land upon Phodia, commanded by First Captain Karlaen, the Shield of Baal. Their mission is to find and secure the planetary governor, whose blood may hold the key to curing the twin curses of the Chapter: the Red Thirst and the Black Rage. But the Spawn of Cryptus, a sinister tyranid creature, is also seeking the governor, and Karlaen stands in its way…