"My name is Warwick Davis. I'm the UK's go-to dwarf." Four years on from Extras - and eight since the last episodes of The Office - Ricky Gervais and Stephen Merchant return to their mockumentary roots with this excruciatingly funny sitcom starring 3ft 6in actor Warwick Davis as a rather down-at-heel version of his real self. Trailed by a camera crew making a documentary about his life as a film star and dwarf talent agent, Warwick - who's been in everything from Return of the Jedi to the Harry Potter movies - has hit hard times and is keen to brush over embarrassing realities and make a good impression. "I want people to see a sophisticated dwarf-about-town who carries himself with dignity. I'm a role model, a bit like Martin Luther King..."

Making viewers feel as uncomfortable about their political correctness as their prejudice is Gervais and Merchant's stock in trade, and the cringe-making moments pile up relentlessly. They also revive a key ingredient of Extras, cramming the series with as many celebrity guest appearances as possible. Liam Neeson gets the lion's share of the self-deprecation tonight, although Extras regular Shaun Williamson also gets to make a familiar contribution.

Interview: Shaun Williamson in Porridge

Stepping into the shoes of Ronnie Barker is not an easy thing for anyone to do, but over the last few months Shaun Williamson, best known as Barry Evans in EastEnders, has been doing just that in a tour that comes to New Wimbledon Theatre next week.

The second sitcom try-out in C4's Comedy Showcase season, and this one packs some more heavyweight comedy credentials. It boasts Ricky Gervais as script editor - a solid gold seal of approval. Disappointingly, there's no sign of former EastEnders Dean Gaffney or Shaun Williamson who manned the phone shop in Extras. This one is staffed by Ashley and Jerwayne (Andrew Brooke and Javone Prince).

Emma Fryer's in it too, still wearing that dazed, sleepwalker expression that she used in BBC2's Home Time.

Tom Bennett is new boy Chris, trying to make his first sale in the cut-throat world of 24-month contracts and impress his sex addict boss (played by Martin Trenaman).

Written, directed and produced by Phil Bowker (who also produced Sharon Horgan's Pulling) I hope this one gets the go-ahead as a series too.

The cast gel together as if they've worked together for years and even manage to turn BNP leader Nick Griffin into joke fodder.