Calgar's Fury

The Realm of Ultramar stands as a shining beacon of order and strength in a galaxy wracked by war and torment. Custodian of this realm, and Chapter Master of the Ultramarines, Marneus Calgar has fought many foes and won countless wars to ensure its borders remain safe. But when an immense space hulk emerges into the Ultramar system, carrying with it the threat of something ancient and terrible, it is Calgar once again who stands in defence of his realm, prepared to meet whatever horrors are aboard and discover the mystery at the heart of the ship dubbed Fury.

Read it because
The Lord of Macragge returns to action in a classic Ultramarines style story – when there's a space hulk with something deadly on board, who else are you going to call but the boys in blue?