Credits

• 2016 · The Last Laugh as Self
• 1992 · Queen Esther as Haman (voice)
• 1991 · The Cabinet of Dr. Ramirez as Fat Man Looking for a Tax Break
• 1990 · Law & Order as William Unger
• 1989 · The Simpsons as Colonel Klink (voice)
• 1986 · Mr. Sunshine as
• 1982 · Matt Houston as Felix Randolph
• 1981 · The Return of the Beverly Hillbillies as C.D. Medford
• 1980 · Steve Martin: Comedy Is Not Pretty as Plato
• 1978 · Vega$ as
• 1977 · The Love Boat as Mr. Perkins
• 1977 · Tabitha as
• 1977 · The Rhinemann Exchange as Franz Altmuller
• 1972 · Assignment: Munich as Insp. Hoffman
• 1972 · Place of Belonging as Narrator
• 1971 · McMillan and Wife as Dr. Ernest Bleeker
• 1971 · McMillan and Wife as Van Doren
• 1970 · Night Gallery as
• 1969 · Wake Me When the War Is Over as Maj. Erich Mueller
• 1968 · The Doris Day Show as Werner Klemperer
• 1968 · Star Spangled Salesman as Chief's Boss
• 1968 · The Wicked Dreams of Paula Schultz as Klaus
• 1967 · Rowan & Martin's Laugh-In as Self
• 1966 · Batman as Colonel Klink
• 1965 · Hogan's Heroes as Wilhelm Klink
• 1965 · Lost in Space as Bolix
• 1965 · Ship of Fools as Lt. Huebner
• 1965 · Dark Intruder as Prof. Malaki
• 1964 · Youngblood Hawke as Mr. Leffer
• 1963 · Bob Hope Presents the Chrysler Theatre as Colonel Wertha
• 1963 · The Dakotas as
• 1962 · Escape from East Berlin as Walter Brunner
• 1962 · General Electric True as
• 1961 · Judgment at Nuremberg as Emil Hahn
• 1961 · Operation Eichmann as Adolf Eichmann
• 1960 · The Case of the Dangerous Robin as Jan Hoveen
• 1960 · Peter Loves Mary as
• 1960 · The Islanders as Michel Serati
• 1960 · Checkmate as Franz Leder
• 1960 · Thriller as Mr. Clark
• 1959 · Adventures in Paradise as Kuberli
• 1959 · The Alaskans as
• 1959 · The Third Man as
• 1959 · Men into Space as
• 1959 · Judgment at Nuremberg as Emil Hahn
• 1959 · One Step Beyond as Herr Bautmann
• 1959 · Rawhide as
• 1958 · Houseboat as Harold Messner
• 1958 · 77 Sunset Strip as
• 1958 · Behind Closed Doors as
• 1958 · Steve Canyon as Linz
• 1958 · The Goddess as Joe Wilsey
• 1958 · The High Cost of Loving as Joseph Jessup
• 1957 · Kiss Them for Me as Lt. Walter Wallace
• 1957 · Maverick as Alex Jennings
• 1957 · Perry Mason as Stefan Riker
• 1957 · Perry Mason as Ulric Zenas
• 1957 · Perry Mason as Police Insp. Hurt
• 1957 · M Squad as Heinrich Ronn
• 1957 · The Thin Man as
• 1957 · Have Gun, Will Travel as
• 1957 · Istanbul as Paul Renkov
• 1956 · The Wrong Man as Dr. Bannay (uncredited)
• 1956 · Five Steps to Danger as Dr. Frederick Simmons
• 1956 · Death of a Scoundrel as Herbert Bauman (Clementi's lawyer)
• 1956 · Flight to Hong Kong as Bendesh
• 1956 · Playhouse 90 as Emil Hahn
• 1956 · Wire Service as Krylov
• 1956 · Tony Awards as Self - Nominee
• 1955 · Matinee Theater as
• 1955 · Alfred Hitchcock Presents as Professor Klopka / Captain Kriza
• 1955 · Alfred Hitchcock Presents as Mr. Ranks
• 1955 · Navy Log as
• 1955 · Gunsmoke as Clifton Bunker
• 1954 · Climax! as
• 1954 · Studio 57 as
• 1953 · General Electric Theater as Mr. Muller
• 1952 · China Smith as
• 1948 · The Philco Television Playhouse as Leopold
• 1948 · The Philco Television Playhouse as