Like almost everyone else on Earth, Danes was transformed into one of the so-called "Master Race" because of the Master's work on the Immortality Gate — and then was re-converted into a human by Rassilon's gauntlet. Immediately following this transformation, Danes and the rest of the household staff fled the Naismith mansion. (TV: The End of Time)
Behind the scenes
Much of this character's spoken role was cut for time, but his major speech was included as a deleted scene in the DVD box set of the 2009 specials. In it, Danes gave Naismith's staff a short lecture, telling them that if the Master was to make the slightest move, he should be shot dead on sight.