Laurence Olivier (1907–1989) was an English actor who, along with his contemporaries Ralph Richardson and John Gielgud, dominated the British stage of the mid-20th century.
 He also worked in films throughout his career, playing more than fifty cinema roles.
 From 1935 he performed in radio broadcasts and, from 1956, had considerable success in television roles.
Laurence Kerr Olivier, Baron Olivier, {'1': ", '2': ", '3': ", '4': "} ( ; 22 May 1907 – 11 July 1989) was an English actor and director who, along with his contemporaries Ralph Richardson and John Gielgud, dominated the British stage of the mid-20th century.
 He also worked in films throughout his career, playing more than fifty cinema roles.
 Late in his career, he had considerable success in television roles.
The Divorce of Lady X is a 1938 British colour romantic comedy film made by London Films; it stars Merle Oberon, Laurence Olivier, Ralph Richardson and Binnie Barnes.
 It was directed by Tim Whelan and produced by Alexander Korda from a screenplay by Ian Dalrymple and Arthur Wimperis, adapted by Lajos Bíró from the play "Counsel's Opinion" by Gilbert Wakefield.
 The music score was by Miklós Rózsa and Lionel Salter and the cinematography by Harry Stradling.
Sir Ralph David Richardson (19 December 1902 – 10 October 1983) was an English actor who, along with his contemporaries John Gielgud and Laurence Olivier, dominated the British stage of the mid-20th century.
 He worked in films throughout most of his career, and played more than sixty cinema roles.
 From an artistic but not theatrical background, Richardson had had no thought of a stage career until a production of "Hamlet" in Brighton inspired him to become an actor.
 He learned his craft in the 1920s with a touring company and later the Birmingham Repertory Theatre.
 In 1931 he joined the Old Vic, playing mostly Shakespearean roles.
 He led the company the following season, succeeding Gielgud, who had taught him much about stage technique.
 After he left the company, a series of leading roles took him to stardom in the West End and on Broadway.
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 What a Lovely War is a 1969 British comedy musical film directed by Richard Attenborough (in his directorial debut), with an ensemble cast including Maggie Smith, Dirk Bogarde, John Gielgud, John Mills, Kenneth More, Laurence Olivier, Jack Hawkins, Corin Redgrave, Michael Redgrave, Vanessa Redgrave, Ralph Richardson, Ian Holm, Paul Shelley, Malcolm McFee, Jean-Pierre Cassel, Nanette Newman, Edward Fox, Susannah York, John Clements, Phyllis Calvert and Maurice Roëves.
Q Planes (known as Clouds Over Europe in the United States) is a 1939 British comedy spy film starring Ralph Richardson, Laurence Olivier and Valerie Hobson.
 Olivier and Richardson were a decade into their 50-year friendship and theatrical collaboration and had just completed "Othello", with Richardson in the title role and Olivier as Iago, when this film was made.
 The film was produced by Irving Asher, an American, with British film impresario Alexander Korda as executive producer.
Khartoum is a 1966 film written by Robert Ardrey and directed by Basil Dearden.
 It stars Charlton Heston as British Gen. Charles "Chinese" Gordon and Laurence Olivier as the Mahdi (Muhammad Ahmed), with a supporting cast that includes Richard Johnson and Ralph Richardson.
 The film is based on historical accounts of Gordon's defence of the Sudanese city of Khartoum from the forces of the Mahdist army, during the Siege of Khartoum.
 The opening and closing are narrated by Leo Genn.
Sir Ralph Richardson (1902–1983) was an English actor who appeared on radio, film, television and stage.
 Described by "The Guardian" as "indisputably our most poetic actor", and by the director David Ayliff as "a natural actor ... [who] couldn't stop being a perfect actor", Richardson's career lasted over 50 years.
 He was—in the words of his biographer, Sheridan Morley—one "of the three great actor knights of the mid-twentieth century", alongside Laurence Olivier and John Gielgud.
Sir Arthur John Gielgud ( ; 14 April 1904 – 21 May 2000) was an English actor and theatre director whose career spanned eight decades.
 With Ralph Richardson and Laurence Olivier, he was one of the trio of actors who dominated the British stage for much of the 20th century.
 A member of the Terry family theatrical dynasty, he gained his first paid acting work as a junior member of his cousin Phyllis Neilson-Terry's company in 1922.
 After studying at the Royal Academy of Dramatic Art he worked in repertory theatre and in the West End before establishing himself at the Old Vic as an exponent of Shakespeare in 1929–31.
Insult is a 1932 British drama film directed by Harry Lachman and starring Elizabeth Allan, John Gielgud and Hugh Williams.
 It is an adaptation of a play by Jean Fabricus.
 It is a melodrama set in the French Foreign Legion in North Africa.

Question: Which Insult actor along with Ralph Richardson and Laurence Olivier dominated the British stage for much of the 20th century?
Answer: John Gielgud