Aghast by the disheartening evidence brought forth by his fellow brother astartes, Gabriel Angelos pursues his closest of battle-brothers. To find the truth. But what Gabriel finds may push him to the very brink of his loyalty to the Holy-God Emperor to defeat. Riddled with grief from a past of service in the Emperor's name, Gabriel hunts down his accused brother, but will the past that haunts him mind ultimately be the cause for his death?