Sellers and "The Goon Show" were a strong influence on the Monty Python performers, with John Cleese calling him "the greatest voice man of all time", adding, "If he could listen to you for five minutes, he could do a perfect impersonation of you." The Goons were imported to the United States by the NBC program "Monitor", which played recorded Goon show episodes starting in 1955. The American comedy troupe the Firesign Theatre also cited the Goons as a big influence on their radio comedy style.