Later, his medical studies at University College Dublin were cut short when he was invited to join the players at the Abbey Theatre.

[1] On 4 December 1947 at St Patrick's Church, Soho Square, London,[2] he married the English actor Barbara White (1923–2013) whom he acted with in The Voice Within (1946) and Mine Own Executioner (1947).

[3] Moore began his acting career at the Abbey Theatre in Dublin, and made his British stage debut at the age of 19 as Heathcliff in a production of Wuthering Heights.

Then he has six-feet-two of brawn, a mobile photogenic face, rich expressive eyes, and ability to adapt himself to any type of role – ultra romantic or the last word in villainy.

"[5]Adopting the stage name Kieron Moore, he was cast in a leading role in A Man About the House (1947), directed by Leslie Arliss.

[8] Korda then gave Moore the plum role of the suave Count Vronsky in Julien Duvivier's production of Anna Karenina (1948), which starred Vivien Leigh and Ralph Richardson.

Moore was invited to Hollywood, where in 1951 he made two films, playing Uriah the Hittite in the biblical epic David and Bathsheba, supporting Gregory Peck and Susan Hayward, and a French Foreign Legion corporal in Ten Tall Men, starring Burt Lancaster.

He gave an impressive performance in the comedy-thriller The League of Gentlemen (1960), playing a homosexual former fascist and army officer recruited to take part in a big robbery.

Moore did two more for Yordan, The Thin Red Line (1964), and Crack in the World (1965) (the second disaster movie after 'Triffids' where his character's romantically linked to Janette Scott), then Son of a Gunfighter (1965) (all second-billed and all shot in Spain) and Arabesque (1966).

Boy Meets Girl, Department S, Vendetta, Jason King, The Adventurer, The Protectors and Randall and Hopkirk (Deceased)—the last of these was in the episode "When the Spirit Moves You", as the villain Miklos Corri.

[13] He last worked for television, providing voice-overs for Muiris Mac Conghail's RTÉ documentaries about the Aran Islands and the Blaskets.

Moore retired in 1994 to the Charente-Maritime in France, where he joined the church choir, became a hospital visitor, and enjoyed reading French, Spanish, English and Irish literature.

[14] He was survived by his wife and former actress Barbara White, their daughter Theresa (Soeur Miriame-Therese) and sons Casey, Colm and Seán.