8 Out Of 10 Cats Does Countdown Season 25 is yet to be announced by Channel 4

Jimmy Carr hosts a combination of the comedy panel show and the long-running words and numbers quiz, inviting Jon Richardson and Jack Dee to take on Lee Mack and Rose Matafeo in a festive-themed edition. They're joined by guests Stevie Martin and Joe Wilkinson, and Countdown regulars Susie Dent and Rachel Riley.

Jimmy Carr hosts a combination of the comedy panel show and the long-running words and numbers quiz, with Jonathan Ross and Russell Kane taking on Alan Carr and Judi Love. Regular Countdown mathematician Rachel Riley and lexicographer Susie Dent are on hand to adjudicate, while Josh Jones is in Dictionary Corner.

Jimmy Carr hosts the comedy words-and-numbers quiz as Roisin Conaty and Joe Wilkinson take on Jon Richardson and Nabil Abdulrashid. Regular Countdown mathematician Rachel Riley and lexicographer Susie Dent are on hand to adjudicate, aided by David O'Doherty in Dictionary Corner.

Jimmy Carr hosts the comedy words-and-numbers quiz as Richard Ayoade and Sara Pascoe take on Jon Richardson and Chris McCausland. Regular Countdown mathematician Rachel Riley and lexicographer Susie Dent are on hand to adjudicate, aided by Morgana Robinson in Dictionary Corner.

Jimmy Carr hosts and regular Countdown mathematician Rachel Riley and lexicographer Susie Dent are on hand to adjudicate as Jon Richardson and Jo Brand take on Joe Wilkinson and Jamali Maddix. Rachel Parris is in Dictionary Corner.

Jimmy Carr hosts and regular Countdown mathematician Rachel Riley and lexicographer Susie Dent are on hand to adjudicate Alan Carr and Harriet Kemsley play against Jonathan Ross and Maisie Adam. Huge Davies is in Dictionary Corner.

Jimmy Carr hosts a combination of the comedy panel show and the long-running words-and-numbers quiz, with Jon Richardson and Lucy Beaumont taking on Richard Ayoade and Joe Wilkinson. Regular Countdown mathematician Rachel Riley and lexicographer Susie Dent are on hand to adjudicate, alongside Dictionary Corner guest Finlay Christie.

In his final appearance the late Sean Lock is joined by Harry Hill as they take on Jon Richardson and Rosie Jones. Mr Swallow, aka Nick Mohammed, is in Dictionary Corner. Jimmy Carr hosts, while regular Countdown mathematician Rachel Riley and lexicographer Susie Dent are on hand to adjudicate.

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.

Jimmy Carr hosts, as Lee Mack and Joe Wilkinson take on Jon Richardson and Jessica Knappett. Comedian Nigel Ng is in Dictionary Corner. Regular Countdown mathematician Rachel Riley and lexicographer Susie Dent are on hand to adjudicate.

Jimmy Carr hosts, as Roisin Conaty and Asim Chaudhry take on Jon Richardson and Josh Widdicombe. Bill Bailey is in Dictionary Corner. Regular Countdown mathematician Rachel Riley and lexicographer Susie Dent are on hand to adjudicate.

Jack Dee and Tom Allen take on Jon Richardson and Judi Love. With Dr John Cooper Clarke.

Jimmy Carr hosts as Roisin Conaty and Kiri Pritchard-McLean take on Jon Richardson and Rob Beckett. Comedian Huge Davies is in Dictionary Corner. Regular Countdown mathematician Rachel Riley and lexicographer Susie Dent are on hand to adjudicate.

Jimmy Carr hosts an edition packed with festive surprises. Countdown regulars Susie Dent and Rachel Riley are on hand to help maintain order as Jon Richardson and Sarah Millican take on Lee Mack and Jason Manford. They are joined by guests Nick Mohammed and Joe Wilkinson.

Jon Richardson and Joe Wilkinson take on Lee Mack and Katherine Ryan in the comedy words-and-numbers game, while The Brett Domino Trio join Susie Dent in Dictionary Corner. Hosted by Jimmy Carr, with Rachel Riley looking after the numbers and letters.

Jimmy Carr hosts the game show mash-up, with Rachel Riley and Susie Dent. Jon Richardson and Lucy Beaumont take on Roisin Conaty and Joe Wilkinson in the comedy words-and-numbers game, while Bec Hill joins Susie Dent in Dictionary Corner.

Jimmy Carr hosts the game show mash-up, with Rachel Riley and Susie Dent. Jon Richardson and Sara Pascoe take on Sean Lock and Richard Ayoade. Nick Helm joins Susie in Dictionary Corner.

Sean Lock and Harriet Kemsley take on Jon Richardson and Joe Lycett in the words-and-numbers game, while Mat Ewins joins Susie Dent in Dictionary Corner.

Jimmy Carr hosts the game of words and numbers, with Rachel Riley and Susie Dent. Sean Lock and Paul Foot play against Jon Richardson and Angela Barnes while John Cooper Clarke joins Susie in Dictionary Corner.

Katherine Ryan and Joe Lycett take on Johnny Vegas and Sean Lock in the words-and-numbers game, while would-be novelist Christopher Bliss joins Susie Dent in Dictionary Corner. Hosted by Jimmy Carr with Rachel Riley looking after the numbers and letters.

Jimmy Carr hosts a festive-themed edition of the words and numbers game, with Rachel Riley and Susie Dent. Jon Richardson and Sarah Millican face off against Sean Lock and David Mitchell. David O'Doherty joins Susie in Dictionary Corner.

A chance to watch top moments, as comedians including Kevin Bridges, Roisin Conaty, Joe Lycett and Joe Wilkinson join Jimmy Carr, Susie Dent and Rachel Riley.

A chance to watch top moments from the comedy game-show mash-up, with guests including Richard Ayoade, Aisling Bea, Alan Carr, David Mitchell, Katherine Ryan and Johnny Vegas.

Jimmy Carr hosts as Sean Lock and Daisy May Cooper take on Richard Ayoade and Ivo Graham. Adam Buxton joins Susie Dent in Dictionary Corner and Joe Wilkinson assists Rachel Riley.

Jimmy Carr hosts as Jon Richardson and Tom Allen take on Sean Lock and Rosie Jones. With Dictionary Corner guest Adam Riches as Sean Bean, plus experts Susie Dent and Rachel Riley.

Jimmy Carr hosts as Sean Lock and Kerry Godliman take on Jon Richardson and Joe Wilkinson. With Susie Dent, Rachel Riley and Dictionary Corner guest Mr Swallow, aka Nick Mohammed.

Jimmy Carr hosts as Sean Lock and Harriet Kemsley take on Jon Richardson and Chris McCausland. Nick Helm is with Susie Dent in Dictionary Corner. Joe Wilkinson joins Rachel Riley at the numbers board.

Jimmy Carr hosts as Sean Lock and Kevin Bridges take on Jon Richardson and Victoria Coren Mitchell in the classic words-and-numbers quiz. Regular Countdown maths whizz Rachel Riley and words guru Susie Dent are on hand to adjudicate, with Susie joined in Dictionary Corner by Spencer Jones.

Jimmy Carr hosts as Sean Lock and Miles Jupp take on Jon Richardson and Sophie Duker. Lee and Dean join Susie Dent in Dictionary Corner.

Sean Lock and Joe Wilkinson take on Jon Richardson and Kiri Pritchard-McLean. The Brett Domino Trio join Susie Dent in Dictionary Corner. Jimmy Carr hosts. Rachel Riley takes care of the numbers.

Sean Lock and Harry Hill take on Jon Richardson and Rose Matafeo, while Alex Horne and the Horne Section join Susie Dent in Dictionary Corner. Hosted by Jimmy Carr with Rachel Riley looking after the numbers and letters.

Jimmy Carr hosts a festive edition of the combination of the comedy panel show and the long-running words and numbers quiz, with Sean Lock and Bob Mortimer taking on Jon Richardson and Lucy Beaumont. Regular Countdown mathematician Rachel Riley and lexicographer Susie Dent are on hand to adjudicate with guests Adam Buxton and Joe Wilkinson.

Sean Lock and Katherine Ryan take on Jon Richardson and Joe Wilkinson in the classic words-and-numbers quiz, while Adam Riches as Sean Bean joins Susie Dent in Dictionary Corner. Hosted by Jimmy Carr, with regular Countdown mathematician Rachel Riley looking after the numbers and letters.

Sean Lock and Harriet Kemsley take on special guest team captain Alan Carr and Catherine Tate, while Adam Buxton joins Susie Dent in Dictionary Corner.

Sean Lock and Sara Pascoe take on special guest team captain Alan Carr and Tom Allen in the classic words-and-numbers quiz, while Rosie Jones joins Susie Dent in Dictionary Corner. Hosted by Jimmy Carr, with regular Countdown mathematician Rachel Riley looking after the numbers and letters.

Sean Lock and Rob Beckett take on special guest team captain Alan Carr and Sarah Millican. Nick Mohammed is in Dictionary Corner with Susie Dent. With Jimmy Carr and Rachel Riley.

Sean Lock and Joe Wilkinson take on Jon Richardson and Sara Pascoe. Sam Simmons is in Dictionary Corner, while maths whizz Rachel Riley looks after the letters and numbers.

Sean Lock and Victoria Coren Mitchell take on Jon Richardson and James Acaster, while Morgana Robinson joins wordsmith Susie Dent in Dictionary Corner.

Sean Lock and Miles Jupp take on Jon Richardson and Rose Matafeo, while Vic Reeves joins Susie Dent in Dictionary Corner. Hosted by Jimmy Carr, with regular Countdown mathematician Rachel Riley looking after the numbers and letters.

Sean Lock and Joe Wilkinson take on Jon Richardson and Harriet Kemsley in the classic words and numbers quiz. James Veitch joins Susie Dent in Dictionary Corner.

Sean Lock and Michelle Wolf take on Jon Richardson and Rob Beckett in the classic words and numbers quiz. Spencer Jones joins Susie Dent in Dictionary Corner, while maths whizz Rachel Riley looks after the numbers.

Sean Lock and David Mitchell take on Jon Richardson and Sara Pascoe. Plus, Ellie White and Natasia Demetriou join Susie Dent in Dictionary Corner, while maths whizz Rachel Riley looks after the numbers.

Sean Lock and Joe Wilkinson take on guest captain Richard Ayoade and Aisling Bea. Plus special guest Tom Allen joins Susie Dent in Dictionary Corner, while maths whizz Rachel Riley looks after the numbers.

Jimmy Carr hosts a brand new episode as Sean Lock and Claudia Winkleman take on Jon Richardson and Henning Wehn. Plus, Nick Helm joins Susie Dent in Dictionary Corner, while maths whizz Rachel Riley looks after the numbers.

Sean Lock and Johnny Vegas take on guest captain Alan Carr and Lou Sanders. Plus The Brett Domino Trio join Susie Dent in Dictionary Corner, while maths whizz Rachel Riley looks after the numbers.

Jimmy Carr hosts a very special Christmas edition, as Sean Lock and Kathy Burke take on Jon Richardson and David Mitchell. Plus James Acaster and Joe Wilkinson join Countdown regulars Susie Dent and Rachel Riley for plenty of festive surprises.

Sean Lock and Roisin Conaty take on guest captain Alan Carr and Joe Lycett in the classic words and number quiz. Spencer Jones joins Susie Dent in Dictionary Corner.

Sean Lock and Kevin Bridges take on Joe Wilkinson and Victoria Coren Mitchell. Adam Kay joins Susie Dent in Dictionary Corner.

Jimmy Carr hosts as Sean Lock and Richard Ayoade take on Jon Richardson and Jessica Knappett. Plus special guests Alex Horne and the Horne Section.

Sean Lock and Phil Wang take on guest captain Alan Carr and Harriet Kemsley in the classic words and number quiz. David O'Doherty joins Susie Dent in Dictionary Corner.

Jimmy Carr hosts a brand new episode of 8 Out of 10 Cats Does Countdown, as Sean Lock and Rob Beckett take on Jon Richardson and Claudia Winkleman. Plus special guests Mr. Swallow and Joe Wilkinson join Countdown regulars Susie Dent and Rachel Riley for the classic words and numbers quiz.

Sean Lock and Miles Jupp take on guest captain Alan Carr and Roisin Conaty in the classic words and number quiz. Ivan Brackenbury joins Susie Dent in Dictionary Corner.

Jimmy Carr hosts a brand new episode with Sean Lock and Katherine Ryan who take on Jon Richardson and Joe Wilkinson in the classic words and number quiz. Dr. John Cooper Clarke joins Susie Dent in Dictionary Corner, while maths whizz Rachel Riley looks after the numbers.

Katherine Ryan guest hosts a very special all female edition celebrating 100 years of women's suffrage. Roisin Conaty and Jessica Hynes take on Sara Pascoe and Lolly Adefope in the classic words and numbers quiz. Morgana Robinson appears in character as Natalie Cassidy alongside Susie Dent in Dictionary Corner, while maths whizz Rachel Riley looks after the numbers.

Jimmy Carr hosts as Johnny Vegas and Rhod Gilbert take on Joe Wilkinson and Roisin Conaty, Tom Allen is in Dictionary Corner.

Jimmy Carr hosts a brand new series of the words and numbers game. Alan Carr and Josh Widdicombe take on Joe Wilkinson and Sara Pascoe, while Bill Bailey is in with Susie Dent, and Rachel Riley is in charge of the letters and numbers.

Jimmy Carr hosts another new edition of the words and numbers game. Lee Mack and Victoria Coren Mitchell take on Alan Carr and Dane Baptiste. Sam Simmons is in with Susie Dent, and Rachel Riley is in charge of the letters and numbers.

Jimmy Carr hosts a brand new series of the words and numbers game. Jon Richardson and Joe Wilkinson take on guest captain Kevin Bridges and Jessica Knappett. John Cooper Clarke is in with Susie Dent and Rachel Riley is in charge of the letters and numbers.

Jimmy Carr hosts a special Christmas edition packed with comic conundrums, festive surprises and laughs aplenty. Jon Richardson and Catherine Tate team up against Sean Lock and Joe Wilkinson, while Joe Lycett joins Susie Dent in Dictionary Corner, and maths whizz Rachel Riley is in charge of the numbers and letters.

Jimmy Carr hosts a brand new episode of the words and numbers quiz. In this show, guest captain Jason Manford and Joe Wilkinson take on guest captain Lee Mack and Fay Ripley. Alex Horne and The Horne Section are in with Susie Dent, while Rachel Riley presides over the letters and numbers.

Jimmy Carr hosts the new series of the words and numbers quiz. In this show, captain Sean Lock and Vic Reeves take on captain Jon Richardson and Sara Pascoe. David O'Doherty joins Susie Dent in Dictionary Corner, while Rachel Riley takes care of the letters and numbers.

Jimmy Carr hosts the new series of the words and numbers quiz. In this show, captain Jon Richardson and Jason Manford take on guest captain Alan Carr and Katherine Ryan. Ivan Brackenbury joins Susie Dent in Dictionary Corner, while Rachel Riley takes care of the letters and numbers.

Jimmy Carr hosts the new series of the words and numbers quiz. In this show guest captain Kathy Burke and Roisin Conaty take on guest captain Johnny Vegas and Bob Mortimer. John Cooper Clarke joins Susie Dent in Dictionary Corner, while Rachel Riley takes care of the letters and numbers.

Jimmy Carr hosts a new edition of the panel/quiz show mash-up with Jon Richardson and Cariad Lloyd, who take on guest captain Alan Carr and Kevin Bridges. Elis James and John Robins are in Dictionary Corner.

Jimmy Carr hosts as Sean Lock and Stephen Mangan take on guest captain Richard Ayoade and Katherine Ryan, Bill Bailey is in Dictionary Corner.

Brand new edition hosted by Jimmy Carr with Jon Richardson and Jonathan Ross who take on guest captain Lee Mack and Victoria Coren Mitchell, with Jessie Cave in Dictionary Corner.

Jimmy Carr hosts a new edition of the panel/quiz show mash-up. In this episode, Jon Richardson and Joe Lycett take on Sean Lock and Michelle Wolf, with Adam Riches in Dictionary Corner.

Jimmy Carr hosts this edition of the comedy panel show with team captains Jon Richardson and Alan Carr and guests Romesh Ranganathan, Sarah Millican and John Kearns.

Jimmy Carr hosts a new episode of the panel/quiz show mash-up, as the 8 Out of 10 Cats crew take over the words and numbers quiz. In this edition it's Jon Richardson and Chris Addison against Joe Wilkinson and Katherine Ryan, with David O'Doherty in Dictionary Corner.

The comedy hybrid returns. Jimmy Carr hosts, and it's Jon Richardson and James Acaster versus Lee Mack and Sarah Millican, with John Cooper Clarke in Dictionary Corner.

Jimmy Carr hosts the words and numbers quiz with Jon Richardson and Michelle Wolf who take on guest captain Jonathan Ross and Johnny Vegas. Pappy's is in Dictionary Corner.

Jimmy Carr hosts the words and numbers quiz with Jon Richardson and David Mitchell who take on guest captain Joe Wilkinson and Roisin Conaty. Tom Allen is in Dictionary Corner.

Jimmy Carr hosts the words and numbers quiz with Sean Lock and Joe Wilkinson who take on Jon Richardson and Jayde Adams. David Baddiel is in Dictionary Corner.

Jimmy Carr hosts a new edition of the topical panel game with Jon Richardson and David O'Doherty who take on guest captain Johnny Vegas and Jamie Laing. Holly Walsh joins Susie Dent in Dictionary Corner, while Rachel Riley looks after the numbers and letters.

Jimmy Carr hosts a comedy version of the quiz show. Jon Richardson and Phil Wang take on guest captain Russell Howard and Roisin Conaty. Nick Helm is in Dictionary Corner with Susie Dent, while Rachel Riley looks after the numbers and letters.

Jimmy Carr hosts a new edition of the topical panel game with Sean Lock and Stephen Mangan who take on Noel Fielding and Fay Ripley. The Brett Domino Trio are in with Susie Dent, while Rachel Riley looks after the numbers and letters.

Jimmy Car hosts while Sara Pascoe and Johnny Vegas take on Jon Richardson and Richard Osman. Susie Dent is joined by David O'Doherty in Dictionary Corner, with Rachel Riley and Joe Wilkinson.

Jimmy Carr hosts this festive show with Sean Lock and Kathy Burke who take on Jon Richardson and Russell Howard. Joe Lycett joins Susie Dent in Dictionary Corner, with Rachel Riley and Joe Wilkinson.

Jimmy Carr hosts, David Mitchell and Cariad Lloyd take on Jon Richardson and Russell Howard. Sam Simmons joins Susie Dent in Dictionary Corner, while Rachel Riley flips the tiles.

Jimmy Carr hosts with Sean Lock and Danny Dyer vs Joe Wilkinson and Gabby Logan. David O'Doherty joins Dictionary Corner, with Susie Dent and Rachel Riley.

Jimmy Carr hosts with guest captain Richard Ayoade and Rob Beckett vs Jon Richardson and Claudia Winkleman. Adam Riches joins Dictionary Corner, with Susie Dent and Rachel Riley.

Guest captain Lee Mack and Bob Mortimer take on Sean Lock and Victoria Coren Mitchell. Alex Horne and the Horne Section join Dictionary Corner, with Susie Dent and Rachel Riley.

Jimmy Carr hosts a brand new episode with guest captain David Walliams and Jessica Hynes going up against Jon Richardson and Rhod Gilbert. Sam Simmons joins Countdown's resident lexicographer Susie Dent in Dictionary Corner, while Rachel Riley looks after the numbers and letters.

Jimmy Carr hosts a brand new episode with guest captain Lee Mack and Catherine Tate going up against Sean Lock and Miles Jupp. John Cooper Clarke joins Countdown's resident lexicographer Susie Dent in Dictionary Corner, while Rachel Riley looks after the numbers and letters.

Jimmy Carr returns to host a brand new episode with guest captain David Walliams and Jonathan Ross going up against Jon Richardson and Joe Lycett. Isy Suttie joins Countdown's resident lexicographer Susie Dent in Dictionary Corner, while Rachel Riley looks after the numbers and letters.

Jimmy Carr returns to host a brand new episode with guest captain Claudia Winkleman and Johnny Vegas going up against Jon Richardson and Reginald D Hunter. Sara Pascoe joins Countdown's resident lexicographer Susie Dent in Dictionary Corner, while Rachel Riley looks after the numbers and letters. Joe Wilkinson will also be appearing.

Jimmy Carr hosts with Sean Lock and David Mitchell going up against Jon Richardson and Katherine Ryan. Brett Domino Trio joins Countdown's resident lexicographer Susie Dent in Dictionary Corner, while Rachel Riley looks after the numbers and letters.

Jimmy Carr returns to host a brand new episode with Sean Lock and David O'Doherty who go up against Jon Richardson and Natasia Demetriou. John Kearns joins Countdown's resident lexicographer Susie Dent in Dictionary Corner, while Rachel Riley looks after the numbers and letters.

Jimmy Carr hosts as Sean Lock and Roisin Conaty go up against Jon Richardson and Nish Kumar. Adam Buxton joins Susie Dent in Dictionary Corner, with Rachel Riley.

Jimmy Carr returns to host a brand new episode with Sean Lock and Henning Wehn who go up against Jon Richardson and Victoria Coren Mitchell. Tom Allen joins Countdown's resident lexicographer Susie Dent in Dictionary Corner, while Rachel Riley looks after the numbers and letters with 'help' from Joe Wilkinson.

Katherine Ryan & David Mitchell join team captains Sean & Jon for another round of light-hearted words and numbers fun. Nick Helm assists in dictionary corner.

Jon Richardson takes on team captain Sean Lock in another round of words and numbers chaos with Rebecca Front and Kevin Bridges. Joe Lycett is in the corner with Susie Dent.

Jon Richardson takes on guest team captain Johnny Vegas in another round of words and numbers chaos with Strictly host Claudia Winkleman and comedians Tom Allen & Rob Beckett.

Jimmy Carr, Sean Lock and Jon Richardson are joined by Bob Mortimer and Holly Walsh for more comic innuendos and unpredictable conundrums. Claudia Winkleman stands in for Rachel Riley on letters-and-numbers duty, while Isy Suttie is in Dictionary Corner with Susie Dent is in Dictionary Corner.

Jimmy, Sean, Jon, Rachel and Susie are joined by Vic Reeves, Aisling Bea and David O'Doherty.

Jimmy, Sean, Jon, Susie and Rachel are joined by Isy Suttie, Richard Osman and Alex Horne.

Jimmy, Sean, Jon, Susie and Rachel are joined by Miles Jupp, Sara Pascoe and Sam Simmons.

Jimmy, Sean, Jon, Susie and Rachel are joined by Rob Beckett, Cariad Lloyd and Jamie Laing.

Jimmy, Sean, Jon, Susie and Rachel are joined by Jason Manford, Roisin Conaty and Sam Simmons.

Jimmy Carr hosts this festive edition as Sean Lock and Johnny Vegas take on Jon Richardson and Katherine Ryan. David O'Doherty joins Susie Dent and Rachel Riley.

Jimmy Carr, Sean Lock and Jon Richardson present a special Christmas show. Guests include Kathy Burke, David Baddiel and Alex Horne and the Horne Section. With Susie Dent and Rachel Riley.

This show gets a 1980s makeover as part of Channel 4 80s Night. Jimmy Carr hosts a new edition of the ultimate 80s words and numbers quiz show, launched in 1982. Jon Richardson and special guest captain Lee Mack are joined by celebrity guests Henning Wehn and David O'Doherty. Countdown regular Susie Dent is joined by Vic Reeves in Dictionary Corner, while Rachel Riley provides the letters and numbers with a little 'help' from comedian Joe Wilkinson.

Jimmy Carr hosts this edition with captain Jon Richardson and special guest captain Lee Mack who are joined by celebrity guests Bob Mortimer and Adam Hills. Countdown regular Susie Dent is in Dictionary Corner with help from Alex Horne and the Horne Section while the country's favourite boffin, Rachel Riley, provides the letters and numbers with a little help from comedian Joe Wilkinson.

Jimmy Carr hosts the iconic words and numbers quiz, as 8 Out of 10 Cats team captains Sean Lock and Jon Richardson are joined by celebrity guests Sarah Millican and Chris Ramsey. Countdown regular Susie Dent shares Dictionary Corner with Abandoman, while the country's favourite boffin Rachel Riley dispenses the letters and numbers with a little help from comedian Joe Wilkinson.

Following the success of 8 Out Of 10 Cats Does Countdown earlier in the year, Jimmy Carr, Sean Lock and Jon Richardson once again take on the famous words and numbers quiz.

As part of Channel 4's special 'mash-up' evening, Jimmy Carr hosts the long-running quiz show while Sean Lock and Jon Richardson compete. Will the team get beaten by the fiendish Countdown conundrum?