Ober often appeared in roles as a straight man in farcical circumstances. He made his debut on stage, playing Tom Faulkner in Technique in 1931. He appeared in Lawrence Riley’s Broadway show Personal Appearance (1934) opposite Gladys George.  From 1954 to 1967, he frequently appeared in television series. He played a general determined to find the truth of an alleged desertion and an Indian attack on a fort in the episode “The Vultures” of the ABC/Warner Brothers western series, Sugarfoot.   Ober was twice cast on I Love Lucy, first playing “Arnold” in “The Quiz Show”, and later portraying the Hollywood producer Dore Schary when Schary decided not to play himself in the episode. He made five appearances on Perry Mason, including that of defendant Peter Dawson in the 1960 episode, “The Case of the Treacherous Toupee”, and the dual role of murder victim Sumner Hodge and his brother Adrian Hodge in the 1964 episode, “The Case of the Tandem Target.” He also made four guest appearances in the comedy series Hazel. He had a recurring role as Gen. Wingard Stone in the very early episodes of NBC situation comedy I Dream of Jeannie and appeared in two episodes of McHale’s Navy as tough-as-nails Admiral “Iron Pants” Rafferty.

Ober continued to work as an actor in films. He played the UN ambassador in Alfred Hitchcock’s North by Northwest (1959) whom Roger Thornhill (Cary Grant) meets, in order to clarify who had occupied his mansion. He also played Capt. Dana “Dynamite” Holmes, the neglectful, unsympathetic husband of Karen Holmes (Deborah Kerr), in the film version of From Here to Eternity (1953).  He retired from acting and went into the U.S. diplomatic service, and died while working at the U.S. consulate in Mexico City.  In 1941, Ober married actress Vivian Vance, who portrayed Ethel Mertz in the CBS comedy series I Love Lucy (1951–1957). They divorced in 1959.  Ober died of a heart attack in 1982.