"War in the webway."
- —Book's tag-line
The Master of Mankind is the forty-first volume in the Horus Heresy series of novels.
While Horus' rebellion burns across the galaxy, a very different kind of war rages beneath the Imperial Palace. The Ten Thousand Custodian Guard, along with the Sisters of Silence and the Mechanicum forces of Fabricator-General Zagreus Kane, fight to control the nexus points of the ancient Eldar Webway that lie closest to Terra, infested by daemonic entities after Magnus the Red's intrusion. But with Traitor Legionaries and corrupted Battle Titans now counted among the forces of Chaos, the noose around the Throneworld is tightening, and none but the Emperor Himself can hope to prevail.
- The Master of Mankind (Novel) by Aaron Dembski-Bowden