Talfryn Thomas
From Tardis Wiki, the free Doctor Who reference
Talfryn Thomas (31 October 1922-4 November 1982) appeared in two Doctor Who stories: as Mullins in Spearhead from Space and Dave in The Green Death.
He was a minor regular during the waning series of the British sitcom Dad's Army, which also used the talents of Alan Tilvern and Wendy Richard.