William Dysart (26 November 1929-October 2002) appeared in two Doctor Who television stories: as Alexander McLaren in The Highlanders and Reegan in The Ambassadors of Death.
Dysart's first credit was in three episodes of Emergency – Ward 10, after which he appeared on Softly, Softly, Z-Cars, Randall and Hopkirk (Deceased), Softly, Softly: Taskforce and Oil Strike North. However, he is best known for playing Alec Campbell in four episodes of Survivors.