[2] Following the Second World War, John moved to Britain in 1951 and continued to work in the theatre, appearing on the London stage in productions including Salome (1954), Carson McCullers' play The Member of the Wedding at the Royal Court Theatre (directed by Tony Richardson, 1957), The Merchant of Venice (1962), Measure for Measure (1963) and Othello (at the Old Vic, with Leo McKern and Adrienne Corri in the cast).

John had several small roles in films such as The African Queen (1951), The Heart of the Matter (1953), Simba (1955), Odongo (1956), The Nun's Story (1959), The Sins of Rachel Cade (1961) and Guns at Batasi (1964); all were set in Africa.

Kate Kellaway wrote in The Observer: "It is marvellous to report that, 55 years on, this play, in its original version, holds its own and seems fresh as the day it was written.

It was produced by Donald McWhinnie and Robin Midgley, with a cast led by John himself and including Barbara Assoon, Sylvia Wynter, Lionel Ngakane, Andrew Salkey, Robert Adams, and Sheila Clarke (Boscoe Holder's wife and lead dancer).

[8] He attempted to work in the American film industry, but was limited to minor roles in Assault on a Queen (1966) and Buck and the Preacher (1972).