He played Dr. Watson in the BBC's television adaptations of the Sherlock Holmes stories between 1964 and 1968, and is known for his supporting roles as a solidly reliable English soldier or bureaucrat in several war and historical film dramas.

He grew up in India before attending St Paul's School, London and the Royal Academy of Dramatic Art, where he earned the Leverhulme Exhibition, Northcliffe Scholarship, and the Principal's Medal.

[3] Stock made his stage debut in 1931, and during his career achieved numerous classical and contemporary credits at various distinguished theatres, including the Old Vic and on Broadway, with productions of The Winter's Tale, Macbeth, She Stoops to Conquer, Uncle Vanya.

His film appearances included popular releases such as Brighton Rock (1947), The Dam Busters (1955), Victim (1961), The Great Escape (1963), The Lion in Winter and The Lost Continent (both 1968), and Russian Roulette (1975).

(1971–73), Quiller (1975), Van der Valk (1977), the Doctor Who serial Time Flight (1982), Yes Minister (1982), Tinker Tailor Soldier Spy (1979) and for a BBC dramatisation of A Tale of Two Cities (1980) as well as The Pickwick Papers (1985) as Mr.