Cargill had a long and illustrious career on stage and in television and cinema, and also had some success as a playwright. Father, Dear Father, in which he played a man struggling to raise two teenage girls alone, ran for five years from the late 1960s.
He also played the doctor in Tony Hancock's classic half-hour sketch The Blood Donor. He never married, but one of his series was called The Many Wives Of Patrick. Often in his early career he was cast as the villain - in Top Secret, The Avengers and The Prisoner. Later he played the hero, but always a smooth gentleman with a world-wary air and a flair for comedy.
His play Ring For Catty was developed into the script for Carry On Nurse - and he played in the Carry On films too. Other film work included Help! with the Beatles, Up Pompeii and the last Charlie Chaplin movie, A Countess From Hong Kong.
Cargill's health had been vulnerable since he was knocked down by a car in Australia at the end of last year.
In recent years he had been working for British Airways Playhouse, an international touring company run by Derek Nimmo. Mr Nimmo said yesterday: "He was a most accomplished actor. He could extract a laugh from thin air. Anywhere in the world, whether Hong Kong or Bangkok, he would get a round of applause on his entrance."
Obituary, page 18