[3] During the Second World War Watson was a physical training instructor in the Royal Navy, and his physique was much in evidence in many of his subsequent screen roles.

[4] After the war, his talent as an impersonator resulted in his becoming a regular on BBC radio programmes such as Take it from Here, Hancock's Half Hour and The Clitheroe Kid.

[5][6] He gradually made the transition to television, where his first major role was in Coronation Street, in which he became Elsie Tanner's (Pat Phoenix) first lover.

He appeared as a powerful but shell-shocked ex-soldier in Dr. Finlay's Casebook, in an episode entitled "Not qualified" which formed part of the 8th series of the popular British programme.

Watson appeared in over 70 films, including: On the Beat (1962) in which he played a police sergeant, Peeping Tom, This Sporting Life, Grand Prix, Tobruk, The McKenzie Break, The Devil's Brigade and The Wild Geese (1978), plus in the Music video of Intaferon - Steam Hammer Sam (published 1983).