Diethard Ried

Diethard Reid (ディートハルト・リート, Dītoharuto Rīto), 31 years old (32 at R2), is the head of information, espionage, and public relations for the Black Knights. A graduate of the Imperial Britannia Central University's Faculty of Law, Diethard is a former producer and member of the press staff at Hi-TV, a Britannian television station. Following the appearance of Zero and the announcement of his goals, Diethard joins the Black Knights, wishing to witness and document Zero's campaign to overthrow Britannia and rule the world. Like Kallen Kozuki, he shows fierce loyalty to Zero, whom he views as his source of inspiration.

Diethard has proven himself to be highly perceptive, easily picking up on the likely outcomes of Zero's plans. He recognizes immediately that Zero is responsible for the destruction of the Japan Liberation Front's tanker ship, a fact which Zero never made the organization aware of. When Kallen wonders if he can be trusted, Lelouch replies that Diethard is dedicated to making Zero a god, which makes him predictable and thus easy to control.

Despite possessing some knowledge of who Lelouch is and of his power, Diethard remains loyal. Only when Lelouch is exposed in front of the leaders of the Black Knights does he finally betray him. He claims that he would rather have watched Zero topple Britannia, but will settle for a hero's death instead. A month after the Second Battle of Tokyo, he defects to Schneizel, deciding that Schneizel and his plans are more interesting than Zero's. When Schneizel is fooled by Lelouch and made a slave to his will, he flies into a rage, shooting a Geassed officer dead and holding Lelouch at gunpoint, calling him Zero and proclaiming that he can't live any longer now that his plan is finished, before Schneizel shoots him. In his dying moments, Diethard asks Lelouch to use his Geass on him, to which Lelouch responds that Diethard isn't worthy of it.