Maurice (The Haunting of Malkin Place)

 was was a World War I soldier who disappeared. He turned up again in 1922. His sister Beatrice thought he had shell shock from the war. He heard spirits and ghosts who haunted him in his house. He rescued the Fourth Doctor from drowning in the marsh. He was still 18, the age he was in war. He felt the guilt of not saving Jack. It was shortly after this that he saw a blue light and appeared home. When the Doctor reset time, he died in the battle saving Jack. (AUDIO: The Haunting of Malkin Place)