Heinrich Konrad

 was an old friend of Brigadier Lethbridge-Stewart. He was the leader of the German branch of UNIT. He fell ill before the Brigadier went to Kriegeskind. He fell to Post Traumatic Stress Disorder. His condition was caused from an experiment he conducted on himself, to create a better breed of soldier. It was the chemicals with which he injected himself that increased his psychic powers which created ghosts from the castle's past. He died to save his men. (AUDIO: Old Soldiers)