when did the second kenneth start his comic performance?
In 1954
Kenneth Williams
but his potential as a comic performer gave him his break when he was spotted playing the Dauphin in Bernard Shaw's "St Joan" in the West End, in 1954 by radio producer Dennis Main Wilson. 
what is round the horne? A BBC Radio comedy program who is the director of the program? UNANSWERABLE when was the last season aired? 9 June 1968 who hosted it? Douglas Smith name a few cast members who worked in the program? Kenneth Horne, Kenneth Williams, Hugh Paddick, Betty Marsden and Bill Pertwee
wiki:19681290
Kenneth Williams [SEP] Comic performer
Williams's professional career began in 1948 in repertory theatre. Failure to become a serious dramatic actor disappointed him, but his potential as a comic performer gave him his break when he was spotted playing the Dauphin in Bernard Shaw's "St Joan" in the West End, in 1954 by radio producer Dennis Main Wilson. Main Wilson was casting "Hancock's Half Hour", a radio series starring Tony Hancock. Playing mostly funny voice roles, Williams stayed in the series almost to the end, five years later. His nasal, whiny, camp-cockney inflections (epitomised in his "Stop messing about ... !" catchphrase) became popular with listeners.