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.

Jimmy Carr returns with Sean Lock and Jon Richardson, who are joined by Jonathan Ross and Roisin Conaty. David O'Doherty joins Susie Dent in Dictionary Corner, and Joe Wilkinson 'helps' Rachel Riley.

Jimmy Carr hosts as Sean Lock and Phil Wang take on guest captain Alan Carr and Harriet Kemsley. Plus special guests David O'Doherty and Joe Wilkinson.

Jimmy Carr hosts as Sean Lock and Richard Ayoade take on Jon Richardson and Katherine Ryan. David O'Doherty is in Dictionary Corner with Susie Dent, and Rachel Riley looks after the numbers and letters.

Jimmy Carr hosts the words and numbers game show mash-up, with `Countdown' regulars Rachel Riley and Susie Dent. Roisin Conaty and Joe Wilkinson play against Jon Richardson and Nabil Abdulrashid. David O'Doherty is in Dictionary Corner.