Tanya (The Sound of Drums)

Tanya was a woman on board the Valiant at the time of the Master's assassination of President Winters. She worked on board during the Year That Never Was. During that time, the Master offered to take her to Catrigan Nova as his personal masseuse.

Biography
Tanya was on board the Valiant when the Master, the British Prime Minister under the alias of Harold Saxon, ordered the assassination of President of the United States Arthur Coleman Winters by the Toclafane. She witnessed the Toclafane's invasion of Earth and through the next year was forced to work for the Master on board the Valiant. (TV: The Sound of Drums)

When Jack Harkness destroyed the Master's paradox machine, events reverted to the moment after Winters had been killed. Though all the people on the planet below forgot the events of the past year, Tanya (along with everyone else on board the Valiant) remembered due to the aircraft carrier's position at the "eye of the storm" (as the paradox machine was on board). (TV: Last of the Time Lords)