[1] John Justinian de Ledesma was born in Knightsbridge, London, England, the son of a well-off Argentine rancher.

In 1937, he briefly trained with the Royal Academy of Dramatic Art, but did not like it and soon joined the repertory company of John Gielgud.

[2] In 1938, he auditioned for and was cast the role for which he is perhaps best remembered, Ahmad in the 1940 version of The Thief of Bagdad, opposite Sabu.

After completing the picture, Justin joined the Royal Air Force, serving as a test pilot and flying instructor.

In 1948, he did a stint at the Shakespeare Memorial Theatre, Stratford-on-Avon, appearing in King John, The Merchant of Venice, The Winter's Tale, Othello, Hamlet, and Troilus and Cressida.

Then he had two leading roles, in The Teckman Mystery (1954) with Margaret Leighton and The Man Who Loved Redheads (1955) with Moira Shearer.

Fox called him back for Untamed (1955) and Warwick Films used him in Safari (1956) with Victor Mature.

(1971), was in Old Fruit (1974), A Man And His Wife (1974) Later films included Ken Russell's Savage Messiah (1972), Lisztomania (1975) and Valentino (1977).