Denk’s list of acting credits begins in the 1930s, with films such as The Love Hotel (1933, as Lilo), Escapade (1936, as Vera, the bride) and the comedy Peter, Paul and Nanette (1935, as Adele), in which she was described as “a slender brunette, especially attractive as a pert maid” in a 1940 New York Times review.
Denk was part of a circle that included writer Klaus Mann and famous actor/director Gustaf Gründgens.
Among collaborations between Gründgens and Denk is a 1948 stage production of Anton Chekhov’s The Seagull, in which they starred as Trigorin and Irina.
In the 1950s, Denk began appearing in television roles, highlighted by a performance as Margot in Besuch aus der Zone [de] (1958), and Leonida in Ein Tag in Paris (1966), in which Denk co-starred with Horst Tappert, who in 1975 would invite her to appear in an episode of his popular and long-running hit series, Derrick (TV series).
Denk also appeared as Frau Price-Ridley in a popular adaptation of Agatha Christie’s The Murder at the Vicarage, produced in German as Mord im Pfarrhaus (1970).