For a thousand years, the Sabbat Worlds have been lost to the Imperium, claimed by the dread powers of Chaos. Now, a mighty crusade seeks to return the sector to Imperial rule. The Space Marines of the Iron Snakes strike against heretic enclaves. Astra Miltarum units such as the Volpone Bluebloods defend worlds from the ruinous hordes. The forces of the enemy – the vicious Blood Pact and Sons of Sek – fight amongst themselves for the honour of facing their foes. And at the forefront of the crusade are Colonel-Commissar Ibram Gaunt and the Tanith First and Only – better known as Gaunt's Ghosts.