Little Britain stars David Walliams and Matt Lucas have unveiled a host of new characters in a bid to conquer America.

The comedy duo's six-part series, Little Britain USA,  will see the return of some of familiar faces, including Vicky Pollard, as well as fresh creations.

The show, which will air on HBO in September, stars muscle-clad Tom and Mark, characters described by Walliams as 'possibly the most outrageous we've ever done'.

Hey y'all: David Walliams and Matt Lucas as American jocks Tom and Mark in Little Britain USA

They are a take on American jocks, who frolicked naked in the gym while boasting about their latest female conquests. 

But the tanned and buff double act have, er, surprise packages in store which will no doubt shock viewers.

Lucas also frocks up to play Ellie-Grace, a misguided child beauty pageant hopeful who is spurred on by her pushy mother, played by cross-dressing Walliams.

New arrivals: Misguided beauty pageant hopeful Ellie-Grace and her pushy mother

Generation gap: Sweet American teen Conor and his grandmother Mildred

Other characters include Conor and Mildred, an American boy from the Deep South and his grandmother, and Bing Gordyn, the eighth man on the moon.

Bing, Lucas explains, is bitter 'because all his glories are behind him and he's obsessed about the lack of recognition he gets compared to the other astronauts.

Bitter: Bing Gordyn, the eighth astronaut on the moon, is Lucas' favourite new character

'He's my favourite new character and David plays him brilliantly.'

Friends star David Schwimmer directs some episodes, while US actress Rosie O'Donnell makes a guest appearance.

Walliams and Lucas say they took America's approach to comedy into account, but it remains to be seen if their distinct brand of humour will translate Stateside.

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Lucas said last week: 'We talked about American comedy being a little cooler and Britain being a bit sadder.'

Added Walliams: 'I think we make ourselves look maybe stupid in Britain a little bit more than being cool.'

'But also we're not afraid to dress as women which is a little bit rarer in American comedy.'

Little Britain USA will air on HBO in September and later in the year on the BBC.

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