The head of the Black Shields, Endrid Haar, is betrayed. His own like-minded people turned against him, handing over the chained former Dog of War into the hands of the legionnaires of the Sons of Horus and promising to return the weapons of mass destruction captured on Zan in exchange for their own lives. Endrid and his former friend Erud Van will have to endure the ordeal, torture and torture of the Sons of Horus in order to walk the line that separates betrayal from loyalty. But when suddenly the sirens start sounding on the ship of the XVI Legion and the vox goes offline, the question inevitably arises: is this a coincidence or is someone putting on an elaborate performance for the Sons of Horus?