8 Out of 10 Cats Does Countdown as part of its 30th anniversary celebrations. Amongst the programmes that were chosen to be merged for the evening of specials, production teams on "Countdown" and "8 Out of 10 Cats" agreed to merge the two formats of their respective programmes together - the crossover between the two formats meant that "Countdown"s arrangement of games would be interspersed with "8 Out of 10 Cats"-style banter. As part of the merger, both Rachel Riley and Susie Dent assumed their roles from the programme, while Jimmy Carr took on the mantle of host, with both Sean Lock and Jon Richardson competing as
Jimmy Carr special episodes known as "The Big Fat Quiz of Everything". Since 2005, Carr has presented the comedy panel show "8 Out of 10 Cats". The show aired on Channel 4 until 2016 when it moved to More4 and then later to E4. Since 2012, Carr has also presented "8 Out of 10 Cats Does Countdown", a combination of his panel show "8 Out of 10 Cats" and daytime quiz show "Countdown". In April 2010, Carr hosted the first British version of a comedy roast show, Channel 4's "A Comedy Roast". On 6 May 2010, he was a co-host of Channel