Borusa

Borusa is a fictional character in the British science fiction television series Doctor Who. He is a Time Lord, and a former teacher of the Doctor.

Borusa appeared in four serials: The Deadly Assassin, The Invasion of Time, Arc of Infinity and The Five Doctors. He was played by a different actor on each occasion (taking advantage of a Time Lord ability originally invented to allow different actors to take over the title role).

He was portrayed in The Deadly Assassin as a good though pretentious person with some political standing on Gallifrey, their home planet. In subsequent episodes he was portrayed with different actor each with somewhat different personalities.

Spoiler warning: Plot or ending details follow.

His final appearance was in The Five Doctors. After many years as Chancellor and then President and several regenerations, he eventually became greedy and attempted to seek immortality through seeking the power of Rassilon. He got it - he became frozen as a living statue.