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: 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: In 1987, Ross and his friend Alan Marke devised a format inspired by Late Night with David Letterman, and after struggling to find a suitable host, Ross stepped in. The resulting show, The Last Resort with Jonathan Ross, made him a star. Other major projects include his chat shows Friday Night with Jonathan Ross and The Jonathan Ross Show, and his stint as the reviewer of the BBC's Film programme. He's also a massive comic book fan; his first foray into the genre, Turf, was published in 2010. But he's also hit the headlines for various controversies over the years, including the notorious Sachsgate, which involved a prank call made by him and Russell Brand to actor Andrew Sachs in 2008.

Career: A regular on TV screens, Kane has performed stand-up on Live at the Electric, Live at the Apollo and Comedy Central at the Comedy Store. He has also appeared on panel shows Mock the Week, 8 Out of 10 Cats and Argumental. Between 2009 and 2011, he co-hosted I'm a Celebrity Get Me Out of Here Now for ITV2. In 2010, he won the main Edinburgh Comedy Award for his show Smokescreens and Castles. His debut novel, The Humorist, was published in 2012. More recently, he presented the travel series Stupid Man, Smart Phone.

Career: Carr made his TV debut as a guest on the ITV lunchtime show Today with Des and Mel. He came to true prominence on Channel 4's The Sunday Night Project with Justin Lee Collins. He makes regular guest appearances on panel shows such as 8 Out of 10 Cats and Never Mind The Buzzcocks and has featured as a panellist on Channel 4's annual Big Fat Quiz of the Year, a staple of the Christmas TV schedules. He has also fronted his own game show, Alan Carr's Celebrity Ding Dong, written his autobiography, and continues to perform stand-up. His Channel 4 show Chatty Man attracts some of the biggest names in showbiz and has been a staple of the Channel 4 schedule since 2009. He also presented a weekly programme on Radio 2 for three years, and fronted game show The Singer Takes It All. In 2016, he hosted Alan Carr's Happy Hour, which was a spin off of Chatty Man.