Martin Donaldson was a World War I veteran living in London in the 1920s.
Martin fought in World War I, consequently losing his leg in battle. After the conflict, he went to live with his sister, Kitty Donaldson.
In 1921, he met the Eighth Doctor and Liv Chenka when his sister Kitty asked the Doctor to check up on him, thinking he was a medical doctor. This led 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 went to see a Buster Keaton film, went to a restaurant and visited the British Museum.
All through this, Martin left items such as a diamond ring, and an alarm clock which aided the Doctor in evading capture by androids. When the androids took the TARDIS, he saved the Doctor, Liv and Kitty by jumping onto a temporal grenade. This caused him to become stuck in a time loop, reliving the events of the previous day, hence the reason for him leaving items to assist the Doctor and Liv. (AUDIO: A Life in the Day)
Personality[]
Martin was brave and resourceful, manipulating events in each loop to his, Kitty, the Doctor, and Liv's benefit and maintaining a list of places in London for him and Liv to visit. He liked comedy films and the British Museum, even if he had previously confused the Elgin Marbles for literal marbles. He fell in love with Liv over the loops, implicitly confessing to her during their lunch together and telling the Doctor as the two of them defused the temporal grenade. (AUDIO: A Life in the Day)