After working as an actor in Teplitz-Schönau and on many German stages, Epp founded The Island theater in 1937. It was located at Parking 6 in Vienna, in a hall of the Palais Eugen. It opened on September 20, 1937 with Paul Claudel's The Guarantor. The theater featured authors such as Aristophanes, Goldoni and Pergolesi. On March 12, 1938, the theatre was occupied by the German SS and closed. Epp occasionally directed the Deutscher Volkstheater, where he also appeared as Christopher in 1938 in Johann Nestroy's Einen Jux will er sich machen. From 1939 to 1941 Epp became partners with Rudolf Haybach, the head of The "Comedy", a theatre group based in Johannesgasse 4. The ensemble of The "Comedy" included Elisabeth Epp, Helmut Janatsch, Hans Brand and a young Josef Meinrad. By March 1940, The "Comedy" had staged ten world premieres for a total of 241 performances and ten guest appearances. The "Comedy" opened in February 1940 with Heinrich Zerkaulen's The Rider under Epps' direction; he also portrayed Rudolf II, "one of the most interesting and impressive theatre evenings of the season". In 1941 a young Oskar Werner debuted in Franz Grillparzer's The Golden Fleece. In 1941, The "Comedy" suffered financial problems, and was sold to the German Labor Front. Epp was unemployed until 1944. After the war, Epp wanted to found a theater called "The Island", managed by the members of The "Comedy" in Johannesgasse. City Council member Viktor Matejka granted the concession and the theatre, renamed by Epp to "The Island in the Comedy", opened on 18 October 1945 with Uncle Vanya by Anton Chekhov. The capacity was 453 seats. Regarding the theatre Elisabeth Epp wrote:
The theater 'The Island' in the comedy is to be opened as a stage adapted to the needs of a cosmopolitan city, placing itself at the service of poetry and performing all the dramas of world literature, which for budgetary reasons are not seen on other Viennese stages does not Performance of which is particularly close to the care of the modern psychological and problematic drama, as an experimental stage for works of modern dramatic literature.
Epp briefly leased the Renaissance Theater in Vienna in 1948 as an additional venue for light fare. However, the expected revenue did not appear and Epp gave the Renaissance Theater in 1949 to Paul Löwinger. Epp then staged as an independent director at the Burgtheater
Vienna Volkstheater (1952-1968)
From 1952 to 1968, Epp directed the Vienna Volkstheater. He staged plays by contemporary dramatists such as Albert Camus, Friedrich Dürrenmatt, Sean O'Casey, Jean Cocteau, Thornton Wilder, Tennessee Williams, William Faulkner, Jean Anouilh, John Osborne, Heinar Kipphardt and great classical productions as well as many new Austrian literature premiers. The motto of the theatre was "It must be dared". Some of the premieres caused quite a stir, such as the staging of Jean-Paul Sartre's The Dirty Hands, which the author tried to prevent with a trip to Vienna, because, in his opinion, it was outdated. In the 1962/63 season, Volkstheater ventured with Mother Courage and her children by Bertolt Brecht. Under the leadership of Hans Weigel and Friedrich Torberg in the so-called "Brecht Boycott " most theatres were closed. The press discussed the Volkstheater's "blockade breakers" premiere on February 23, 1963, with Dorothea Neff and directed by Gustav Manker, who also appeared in The Caucasian Chalk Circle. The next season, the deputy of Rolf Hochhuth in Austrian premiere started fights in the floor. Epp interrupted the premiere in order to go on stage and announce:
Anyone attending this performance may ask themselves if he was somehow complicit in the things described here.