Created in the Emperor's own image, the primarchs had long thought themselves to be princes of the universe and masters of their own destiny - they led the Space Marine Legions in glorious conquest of the galaxy, and no enemy of the Imperium could stand against them. However, even amongst this legendary brotherhood, the seeds of dissent had been sown long before the treacherous Warmaster Horus declared his grand heresy. Gathered within this anthology are four novellas focusing on some of the mightiest warriors and leaders that mankind has ever known - Fulgrim, Alpharius, Lion El'Johnson and Ferrus Manus - and the roles that they may have yet to play in a war which threatens to change the face of the Imperium forever.