Gerardo Luigi "Jerry" Colonna was an Italian-American comedian, singer, songwriter, and trombonist best remembered as the zaniest of Bob Hope's sidekicks in Hope's popular radio shows and films of the 1940s and 1950s. With his pop-eyed facial expressions and walrus-sized handlebar moustache, Colonna was known for singing loudly "in a comic caterwaul," according to Raised on Radio author Gerald Nachman, and for his catchphrase, "Who's Yehudi?", uttered after many an old joke, although it usually had nothing to do with the joke. The line was believed to be named for violin virtuoso Yehudi Menuhin, and the search for Yehudi became a running gag on the Hope show. Colonna played a range of nitwitted characters, the best-remembered of which was a moronic professor. Nachman wrote: Colonna brought a whacked-out touch to Hope's show. In a typical exchange, Hope asks, "Professor, did you plant the bomb in the embassy like I told you?", to which Colonna replied, in that whooping five-alarm voice, "Embassy? Great Scott, I thought you said NBC!"