cast in Ivor Novello's play Comedienne (directed by Murray Macdonald), at the Aldwych Theatre in London. From 26 August 1937 to 12 March 1938, he played Ernest Beevers in J. P. Mitchelhill's adaptation of the J. B. Priestley time play Time and the Conways at the Duchess Theatre in London, and from 17 February to 17 June 1939, he played Sir Patrick Cullen in The Doctor’s Dilemma at the London Mask Theatre, Westminster Theatre and Whitehall Theatre. Of this role, Sieghard Erich Krueger writes that he "acheives a fine effect of crusted and downright integrity." Johns' final film role of the interwar era was as Thomas in the 1939 British adventure thriller film Jamaica Inn, directed by Alfred Hitchcock. Second World War The Second World War ushered in a new era for British theatre and cinema. Johns avoided conscription due to his age, and thus began his career in various roles, though most often as the quirky yet dignified "frightened men" described by Adam Benedick. Among his dozens of film roles were the ultracrepidarian Charlie Wickers in the thriller film Saloon Bar (1940) and the church warden Charlie Sims in the war film Went the Day Well? (1942). In the Second World War propaganda film The Next of Kin (1942), Johns starred as the determined Agent 23 (Mr Arthur Davis), described by Robert Murphy as "the most cautious and effective agent – all the more sinister for being played by the kindly Welshman of so many other films of the period, Mervyn Johns." Following this, Johns played the homicidal maniac Arthur Grimshaw in the black-and-white comedy farce My Learned Friend (1943), the proprietor Rhys in the drama film The Halfway House (1944), and Major John Roberts in the drama film Twilight Hour (1945). Commenting on his role as the fearful architect Walter Craig in the 1945 mystery film Dead of Night, The Independent's Adam Benedick describes his approach as having a "masterly touch". Of Johns' stage work, Benedick writes that he "showed a relish for Restoration comedy, but was also rated a ‘quintessential’ Priestley and Shavian actor in such shows as... Heartbreak House (1943), in which he replaced Robert Donat as Captain Shotover, and as Dolittle in Pygmalion (1947)"; his work of the prewar era was just the same. Less well-known are his roles in Frank Harvey's play Saloon Bar from 15 November 1939 to 30 March 1940 at Wyndham’s