episode, "The Haunted U-Boat", of the series One Step Beyond. Also in 1959, he appeared as a Frenchman in the episode "Fragile" of the Western TV series Have Gun – Will Travel. He received significant notice for his role in the award-winning 1961 film Judgment at Nuremberg. The film presents a fictionalized account of the post-World War II Nuremberg trials, with Klemperer portraying Emil Hahn, a Nazi prosecutor and one of the defendants at the trial. Prior to this, he had a small role in the 1957 Errol Flynn film Istanbul and a pivotal part in the "Comstock Conspiracy" episode of Maverick that same year. He played the title role in the 1961 film Operation Eichmann, opposite his future co-star John Banner. He guest-starred in the first Brian Keith television series, Crusader, a Cold War drama that aired on CBS. During this time, he made three guest appearances on Perry Mason: he played East German murder victim Stefan Riker in the 1958 episode "The Case of the Desperate Daughter"; the East European character Ulrik Zenas in the 1963 episode "The Case of the Two-Faced Turn-a-bout"; and German Swiss Police Inspector Hurt in 1964 in "The Case of a Place Called Midnight". In 1963, Klemperer also portrayed a professor of psychology in "The Dream Book", an episode on the sitcom My Three Sons. Prior to Hogan's Heroes, Klemperer appeared in the 1956 episode 'Safe Conduct' of Alfred Hitchcock Presents, along with John Banner; twice appeared as Hugo on the syndicated romantic comedy series, How to Marry a Millionaire (1957–1959), with Barbara Eden and Merry Anders; and appeared on the "Purple Gang" episode of The Untouchables. He is best known, however, as Colonel Wilhelm Klink: the bungling, cowardly, conceited, and self-serving Kommandant of Stalag 13 on Hogan's Heroes, which was broadcast on CBS from 1965 to 1971. Klemperer, conscious that he would be playing the role of a German officer during the Nazi regime, accepted the part only on the condition that Klink would be portrayed as a fool who never succeeded. According to co-star Richard Dawson, Klemperer supplied his own uniforms. When Klemperer's father, the famous conductor Otto Klemperer, saw his first episode of Hogan's Heroes, he said to his son, "Your work is good, but who is the author of this material?" In addition to the character's bumblings, Klink was also remembered for his excruciatingly bad violin playing. For his