School for Secrets included a supporting role for which Scottish actor from "Dad's Army"?
School for Secrets:  In leading supporting roles were David Tomlinson, Raymond Huntley, Finlay Currie, Richard Attenborough, John Laurie and Michael Hordern. John Laurie: John Paton Laurie (25 March 1897 – 23 June 1980) was a Scottish actor. John Laurie:  He is perhaps best remembered to modern audiences for his role as Private Frazer in the sitcom "Dad's Army" (1968–1977).
John Paton Laurie