Jimmy Carr hosts the game show mash-up, with Countdown regulars Rachel Riley and Susie Dent. Sarah Millican and Nish Kumar take on Jon Richardson and Maisie Adam. David O'Doherty is in Dictionary Corner.

8 Out of 10 Cats Does Countdown Season 21 Episodes...

• s21e01 - Roisin Conaty, Kiri Pritchard-McLean, Rob Beckett, Huge Davies
• s21e02 - Jack Dee, Tom Allen, Judi Love, John Cooper Clarke
• s21e03 - Roisin Conaty, Asim Chaudhry, Josh Widdicombe, Bill Bailey
• s21e04 - Lee Mack, Joe Wilkinson, Jessica Knappett, Nigel Ng
• s21e05 - Sarah Millican, Nish Kumar, Maisie Adam, David O'Doherty
• s21e06 - Sean Lock, Harry Hill, Jon Richardson, Rosie Jones

8 Out of 10 Cats Does Countdown Show Summary

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.