Martin Donaldson

 lived in London after World War I, in which he fought and consequently lost his leg, with his sister Kitty Donaldson. He met the Eighth Doctor and Liv Chenka after Kitty asked the Doctor to check up on him, thinking he was a medical doctor. This lead the Doctor to investigate an unstable time field around Martin, but not before Martin had taken Liv on a tour of London, during which they go to see a Buster Keaton film, go to a restaurant and to the British Museum. All through this Martin leaves items such as a diamond ring, and an alarm clock which aid the Doctor in evading capture by androids. When the androids have taken the TARDIS he saves the Doctor, Liv and Kitty by jumping onto a temporal grenade, this causes him to become stuck in a time loop, reliving the events of the previous day, this being the reason for him leaving items to assist the Doctor and Liv. As he tried to diffuse the grenade with the Doctor he confesses that he has fallen in love with Liv. (AUDIO: A Life in the Day)