Guard 1 (The Deadly Assassin)

A guard was a member of the Chancellery Guard in the Time Lord citadel. When the Fourth Doctor arrived in the citadel and was being pursued by guards, he stopped at a elevator, which opened and revealed the guard. He then held the Doctor at gunpoint and started to move him down the corridor, before being shot and killed by. (TV: The Deadly Assassin)

Behind the scenes
Pat Gorman clearly plays the guard again in part two, although Hilred said he was killed in part one.