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
8 Out of 10 Cats Deal" featuring Carr as host alongside Richardson and Lock aired during another Channel 4 "mash-up night", the story behind it being that Noel Edmonds had been driven to leave when Derren Brown was playing, and was getting all the boxes from lowest to highest. Noel ran away with the £250,000 box, saying that he "spent it all on his shirt". The backstage personnel then took out a hammer and smashed the 'break glass for Jimmy Carr' box, which produced a horn, which was used to call Carr to the set. Joe Wilkinson guest starred as the Banker's assistant. Guests were