8 Out of 10 Cats Does Countdown

Jimmy Carr, Sean Lock and Jon Richardson take on the famous words and numbers quiz. Jimmy Carr hosts proceedings, and Sean Lock faces Jon Richardson in a rematch of the original encounter.David O'Doherty is in Dictionary Corner along with Countdown regular Susie Dent. Meanwhile the country's favourite boffin Rachel Riley provides the letters and numbers with a little help from comedian Joe Wilkinson.