Tambor first moved to repertory theater in Milwaukee, later making his Broadway debut in the 1976 comedy Sly Fox. He appeared in Measure for Measure in the same year. In 1979, he starred in Norman Jewison's ...And Justice For All as a lawyer friend of the protagonist Arthur Kirkland (played by Al Pacino).
In an early TV job, an ad for Avis rent-a-car, he was seen running (huffing and puffing) through an airport, mocking O. J. Simpson's "Go, O. J., go!" ads for Hertz. He has had a significant career in episodic TV, where he made numerous guest appearances on different shows, including Taxi, Kojak, M*A*S*H, The Golden Girls, and Three's Company. In 1979, Tambor got his first role as a main character in television in the short-lived show The Ropers. Throughout the 1980s Tambor had a recurring role on Hill Street Blues playing a defense attorney who eventually becomes a judge. In 1987 and 1988, Tambor appeared as a regular on the prime time ABC series Max Headroom as Murray, Edison's editor.
Beginning in 2003, Tambor starred in the television comedy Arrested Development as George Bluth, Sr. and in some episodes as his twin brother Oscar Bluth. In 2004, Tambor received his fifth Emmy nomination for his work on the show.
A role Tambor began in 2009 is that of the recurring character Len Trexler in the sardonic comedy Archer, an animated television series on the FX network. He is a major love interest to Malory Archer played by Jessica Walter – the two formerly playing husband and wife in Arrested Development.
In February 2014, Amazon premiered its original series Transparent, which stars Tambor as a transgender, divorced, Jewish father-turned-mother of three. Tambor won the Golden Globe Award for Best Actor in a Television Series – Musical or Comedy for his portrayal and thanked the transgender community in the midst of his speech.
|Star vs. the Forces of Evil Staff|