Sheridan Smith and Johnny Vegas join Mr Stink cast

The pair will play the parents of lonely 12-year-old Chloe who befriends pongy local tramp Mr Stink (played by Downton Abbey’s Hugh Bonneville) and invites him to take refuge in the family’s garden shed.

“David is such a brilliant writer, and the character just jumped off the page when I read it,” said Smith. “I can’t wait to work with Hugh and Johnny."

Smith, who was recently seen in ITV1’s biopic Mrs Biggs as well as BBC’s acclaimed drama series Accused, will star as Chloe’s overbearing mother, who is more interested in her own political ambitions than her neglected daughter.

Vegas – who has previously appeared in Ideal, Benidorm and Moone Boy – plays Chloe’s put-upon father, who harbours a mysterious secret of his own…

Little Britain fans can also look forward to an appearance from Walliams himself, playing the British Prime Minister.

The actor and comedian has made a name for himself as a children’s writer in recent years with his debut novel, The Boy in the Dress, followed up by Billionaire Boy and Gangsta Granny. Mr Stink is his second children’s novel, selling 250,000 copies since its release in 2009, and has been adapted for television by Walliams and Doctor Who writer Simon Nye.

The 60-minute comedy will be BBC's first fictional programme to be shot in 3D as part of a two-year experimentation with 3D production and distribution.