Career: Carr began performing on the stand-up circuit, doing up to 300 shows a year for three years, before taking his act to the Edinburgh festival in 2002. This brought him to the attention of TV bosses, and before long he was presenting series such as Your Face or Mine and Distraction. Since then, he's rarely been off TVscreens, hosting the first run of the Friday Night Project, 8 Out of 10 Cats and numerous Channel 4 list shows. He's also made a move into acting, appearing in Alien Autopsy, Confetti, Stormbreaker and Telstar. He is one of Britain's busiest comics and his DVDs are big sellers.

Career: Lock's first professional TV appearance was in 1993, when he appeared in a supporting role alongside Rob Newman and David Baddiel on their signature TV show Newman and Baddiel in Pieces. He toured with the duo as their support act and, as a result, became the first comedian to perform at Wembley Arena. He script-edited the 1998 BBC Two series Is It Bill Bailey? and had his own show on BBC radio, 15 Minutes of Misery. It was later expanded into the half-hour series, 15 Storeys High. He's now a team captain on the panel game 8 Out of 10 Cats. Other game show appearances have come in the likes of The Big Fat Quiz of the Year, Have I Got News for You, QI, and They Think It's All Over. He also hosted his own entertainment show on Channel 4 called TV Heaven, Telly Hell.

Career: In 2003, Richardson won his heat of the BBC New Talent Comedy Search, and a year later did well in the Laughing Horse New Act of the Year competition and J20 Last Laugh Comedy Search. Encouraged by these successes and kind words from Jasper Carrott and Dave Spikey for a performance at the Criterion Theatre in London, his confidence grew. More stand-up followed, including appearances at the Edinburgh Fringe Festival. He went on to feature on numerous radio shows before moving into TV. Richardson appeared on Never Mind the Buzzcocks and Have I Got News For You before becoming a team captain on 8 Out of 10 Cats. He's since published his first book, It's Not Me, It's You! and taken part in various documentaries.

Career: Riley's big break came in 2008 when she was chosen from more than 1,000 applicants to replace Carol Vorderman on Countdown. She presented her first show alongside Jeff Stelling in January 2009, and reached her 1,000th episode in June 2013. Away from the numbers and letters on Countdown, she began co-hosting The Gadget Show alongside Jason Bradbury in June 2013. She was a contestant on Strictly Come Dancing in 2013 and was the fifth celebrity to be eliminated.

Career: He reached the finals of the So You Think You're Funny? talent contest at the 2005 Edinburgh Fringe, when he was just 18. He made his Edinburgh Fringe debut in 2007. Two years later he appeared on BBC One's Michael McIntyre's Comedy Roadshow, which hugely boosted his profile to the extend he played the Glasgow SECC in 2010. His debut DVD was a huge hit and he is now a TV regular.

Career: Alan Bennett's internationally successful play and film The History Boys boosted his profile. He co-hosted Big Brother's Big Mouth in 2007, the same year he re-teamed with Fat Friends' Ruth Jones to pen and star in BBC sitcom Gavin & Stacey, which was a huge, Bafta-winning hit. Corden also worked with Gavin & Stacey's Mathew Horne on sketch show Horne & Corden and the film Lesbian Vampire Killers. In 2010, he fronted a series of comedy chat shows for ITV1 revolving around that year's World Cup. Since then he has hosted Sky1's sporting quiz A League of Their Own and appeared in Doctor Who, The Wrong Mans, The Three Musketeers, One Chance and Gulliver's Travels. He has also been the subject on Piers Morgan's Life Stories and hosted the Brits. He returned to the stage in 2011 in the critically acclaimed One Man, Two Guvnors.

Career: Osman has worked behind the scenes as an executive producer on a number of TV programmes, including Deal or No Deal, 8 Out of 10 Cats, and 10 O'Clock Live. As the UK creative director of TV production company Endemol, he pitched the quiz Pointless to the BBC. As a way of explaining the rules, he played the co-host during a run-through. He was asked to do the role for real when the show was commissioned. Pointless started on BBC Two in 2009 and was an immediate hit. It quickly made the switch to BBC One. Since being in the spotlight on Pointless, he has made guest appearances on QI, Have I Got News for You and Would I Lie to You? He also guest presented an episode of The One Show alongside Alex Jones.