Career: Smith's first professional roles came in the plays Fresh Kills, opposite Christian Slater, and On the Shore of the Wide World. He appeared with Slater again in Swimming with Sharks, and also featured in The History Boys. He was part of the Olivier Award-nominated cast of That Face. His TV roles include The Ruby in the Smoke, The Shadow in the North and Secret Diary of a Call Girl, all alongside ex-Doctor Who assistant Billie Piper. He also starred in political drama Party Animals, and made his debut as the 11th Doctor Who in 2010. He was the youngest actor to play the part, but will bow out at Christmas, when he'll be replaced by Peter Capaldi. Other projects include Christopher and His Kind, Bert and Dickie, Womb, and the forthcoming How to Catch a Monster. He will return to the West End stage in 2014 to play the lead in a musical version of American Psycho.

Career: Armstrong made his film and TV debuts in 1994 in There's No Business and A Breed of Heroes. He was introduced to Ben Miller in 1996 and their subsequent success at the Edinburgh Festival Fringe led to their first sketch series in 1997; they've worked together a number of times since on various projects. Armstrong played the lead in short-lived sitcom Beast. He has also appeared in Birthday Girl (2001), I Saw You, TLC, Saxondale, Life Begins, The Trial of Tony Blair, Mutual Friends, Woody Allen's Match Point (2005) and Scoop (2006). Armstrong was the voice of supercomputer Mr Smith in The Sarah Jane Adventures, appeared in the 2011 Doctor Who Christmas Special and has presented the BBC game show Pointless since 2009. In recent years, he has also voiced Danger Mouse in the revival of the animated series and presented Rome's Invisible City, Land of the Midnight Sun and Don't Ask Me Ask Britain.

Career: Bill started touring with the likes of Phill Jupitus and Mark Lamarr, before forming a double-act in 1989 with Martin Stubbs. His big break came in 1995 with the show Bill Bailey's Cosmic Jam, a performance of which was filmed and broadcast on Channel 4. In 1998, he scooped his own comedy show on the BBC, Is It Bill Bailey?, and enjoyed a series of successful guest slots on shows such as Have I Got News for You. Bill also starred in Dylan Moran's Channel 4 sitcom Black Books, before taking over from Sean Hughes as a captain on Never Mind the Buzzcocks in 2002. He's a regular on quiz show QI, and has also enjoyed other acting roles in the likes of Jonathan Creek and Fifteen Storeys High. His big-screen CV includes the movies Saving Grace and Hitchhiker's Guide to the Galaxy, while his cameo in Hot Fuzz was very well-received. He also continues to tour with his stand-up, selling out arenas all over the world, and has begun a separate career as a presenter of wildlife shows, including the ITV series Baboons with Bill Bailey.

Career: Weir's big break came in 1994 when she began playing various roles in BBC sketch comedy The Fast Show alongside Paul Whitehouse, Charlie Higson and John Thomson. The show had a number of catchphrases and the one mostly attributed to Weir was "Does My Bum Look Big in This?" She later used this as the title for a best-selling book. The Fast Show ran until 1997 and returned in 2000 for a one-off special. Weir went on to star in Posh Nosh, Hana's Helpline, Skins and Doctor Who. More recently, she has appeared in one-off drama Two Doors Down, Midomer Murders and House of Fools.