Much, much better known as an actor (radio, TV and film) he also wrote, though only the one play for the stage. (See doollee.com.)
See his Wikipedia page.
And, at the IMDB, another biography and very, very impressive filmography.
On TV, The Rescue was episode 2 of series 13 of Comedy Playhouse. It is not clear which of the TV and stage versions came first.
The Rescue (1975)
The Rescue (1990)