Maurice Selwyn
From Tardis Wiki, the free Doctor Who reference
Maurice Selwyn (18 July 1919-5 December 1972[1]) played the Custodian in the Doctor Who television story The Krotons. He had previously had an uncredited role as a soldier in The Reign of Terror. (DWM 204)
Selwyn's only other known acting credits were in episodes of The Avengers, Theatre 625 and a 1964 version of The Count of Monte Cristo.