In 2012, two of Channel 4's most popular quizzes - the topical hit 8 Out Of 10 Cats and the cerebral words-and-numbers game Countdown - came to metaphorical blows as the anarchic comedians of the former took on the brainbox format of the latter.
Jimmy Carr was the host, with Sean Lock and Jon Richardson as the contestants. Jimmy was helped by Countdown regulars Susie Dent and Rachel Riley, and hindered by Joe Wilkinson.
The gang returned to play Countdown a second time later in 2012.
In January 2013, as part of the next Channel 4 Mash Up, Jimmy Carr, Jon Richardson and Sean Lock hijacked an episode of Deal or No Deal. A number of comedians joined in, plus Rachel Riley and Susie Dent again. Joe Wilkinson acted as the Banker's assistant.
Since 2013, the show has run regularly with multiple-episode series.
8 Out of 10 Cats Does Countdown - Harriet Kemsley, Chris McCausland, Nick Helm Synopsis and Schedule