Peter Pratt

Peter Pratt, (21 March, 1923 - 11th January, 1995), was the second actor to portray the Master on Doctor Who. His portrayal of an emaciated Master at the end of his regenerative cycle introduced a new element in the ongoing battle between the Doctor and this most dangerous of renegade Time Lords.

Doctor Who Episodes
The Master - The Deadly Assassin, Logopolis (archive footage)