I'm Sorry I Haven't a Clue is a BBC radio comedy panel game. Introduced as "the antidote to panel games", it consists of two teams of two comedians "given silly things to do" by a chairman. The show was launched in April 1972 as a parody of radio and TV panel games, and has been broadcast since on BBC Radio 4 and the BBC World Service, with repeats aired on BBC Radio 4 Extra and, in the 1980s and 1990s, on BBC Radio 2. The 50th series was broadcast in November and December 2007 After a period of split chairmanship in the first series,Humphrey Lyttelton ("Humph") served in this role from the programme's inception until his death in 2008. In April 2008, following the hospitalisation and subsequent death of Lyttelton, recording of the 51st series was postponed. The show recommenced on 15 June 2009 with Lyttelton being replaced by a trio of hosts serving in tandem: Stephen Fry, Jack Dee and Rob Brydon. Dee went on to host all episodes of the 52nd series later that year, and continues in that role. The chairman's script is written by Iain Pattinson, who has worked on the show since 1992.