Four famous contenders pit their knowledge against each other and the clock. The contestants are Joe Pasquale, Roger Black, Tony Audenshaw and Diane Louise Jordan. Show more

Four celebrities face John Humphrys and the black chair. Guests are writer Tony Parsons, actress Diane Parish, astrologer Russell Grant and broadcaster Paul Gambaccini. Show more

Four celebrities face John Humphrys and the black chair. Guests are comedian Ed Byrne, actor Tristan Gemmill, television presenter Anneka Rice and comedian and actor John Bishop. Show more

Four celebrities face John Humphrys and the black chair. Guests are director Michael Winner, newsreader Mishal Husain, comedian Dom Joly and actor and satirist John Bird. Show more

Four celebrities face John Humphrys and the black chair. Guests are Strictly dancer Darren Bennett, DJ Stuart Maconie, psychologist Dr Linda Papadopoulos and actor Andrew Lancel. Show more

Celebrities face John Humphrys and the black chair. Newsreader Alastair Stewart, naturalist Steve Backshall, Radio 1 DJ Comedy Dave Vitty and the entrepreneur Saira Khan compete. Show more

Four celebrities face John Humphrys and the black chair. Guests are Stewart Lee, John Thomson, Sascha Kindred and Matthew Lewis. Show more

Four celebrities face John Humphrys and the black chair. Guests are swimmer Mark Foster, actor and writer Nigel Planer, chef Ching He Huang and broadcaster John Suchet. Show more

Four celebrities face John Humphrys and the black chair. Guests are singer Beverley Knight, snooker player John Higgins, politician Michael Howard and weatherman Alex Deakin. Show more

Four celebrities face John Humphrys and the black chair. Musician Goldie, presenter Paul O'Grady, former badminton player Gail Emms and broadcaster Loyd Grossman compete. Show more