Celebrities take on the ultimate intellectual challenge.
John Humphrys presents the celebrity version of Britain's toughest quiz.
Series 9, Show 1
Series 9, Show 2
Series 9, Show 3
Series 9, Show 4
Series 9, Show 5
Roux/Hynes/Hannon/Sopel
Series 9, Show 7
Series 9, Show 8
Series 9, Show 9
Series 9, Show 10
More celebrities brave the famous black chair.
