Eugene Tracy "Gene" Twombly (April 27, 1914 – October 17, 1968) was the sound effects director on several radio shows, including The Jack Benny Show, where his wife, actress Bea Benaderet, played telephone operator Gertude Gearshift. Throughout the show, Jack Benny and his cast often referred to "Twombly, the sound effects man." Eventually, a character named Twombly (voiced by Mel Blanc) appeared on the show, as an inept sound effects man who was constantly interrupting Benny and his cast with impromptu sound effects.

Later, while Bea Benaderet was co-starring in the Beverly Hillbillies as Cousin Pearl, a character, Dr. Eugene Twombly, was introduced as an overly-curious, bedazzled and befuddled psychiatrist, unable to grasp (or get them to overcome) their extremely simple ways. This was a two-episode feature, and arguably, two of their funniest episodes.

Gene Twombly was Bea Benaderet's second husband. He died of a heart attack on October 17, 1968, the day of Benaderet's funeral, four days after her death. She had been ill with lung cancer for more than a year. They are interred together at Valhalla Memorial Park Cemetery (Mausoleum of Hope, Row C, Crypt 34) in North Hollywood, California.