David Mitchell and Robert Webb are to return to BBC Radio 4 for a brand new, fifth series of the award-winning sketch show That Mitchell & Webb Sound.

The duo first launched That Mitchell & Webb Sound ten years ago, with the fourth and - to date - most recent series of the sketch show finishing in September 2009.

With no new series for four years, it was widely assumed that the double-act had finished with the format, making today's news of a Series 5 commission somewhat unexpected.

Confirming the news Mitchell & Webb are to return to radio, the BBC says: "Listeners are in for a treat as they return to the BBC Radio 4 airwaves after a four-year hiatus, with their distinctive and lopsided views on the world through satirical sketches and surreal characters."

The first series of That Mitchell & Webb Sound, broadcast in 2003, became an overnight cult hit thanks to recurring sketches like Big Talk, the Alcoholic Snooker Commentators, the Lazy Drama Writers and The Surprising Adventures of Sir Digby Ceaser-Salad, alongside many more one-off ideas. Across its six year run, the programme also picked up multiple Sony Radio Academy awards and other prizes.

The radio show spun-off into a TV adaptation in 2006, with That Mitchell And Webb Look appearing on BBC Two. The BAFTA-winning television version has also run for four series to date, with the last series broadcast in 2010.

However, it seems the double-act now want to return to the radio format. The new episodes will star the same ensemble cast that launched the show, with James Bachman and the much in-demand Olivia Colman confirmed for the new run.

The BBC explain: "After some time away from radio sketches, the duo realised how much they had missed making the show, so they decided to get the old gang back together. James Bachman, aka Bleak Expectations' Harry Biscuit, will again be part of the cast and the duo are delighted that the fantastic Olivia Colman will be joining the fold once again."

David Mitchell jokes: "It's great to return to Radio 4 now that we're old enough to listen to it."

Robert Webb adds: "I love doing radio, mainly because you don't have to do the actions. David does the actions anyway and I respect his process. Although waiting for him to change costumes can be irksome."

Many of the writing talent involved in That Mitchell & Webb Sound have gone on to join the ranks of today's most in-demand comic writers. Amongst those with writing credits during the first four series are Mark Evans (Bleak Expectations), John Finnemore (Cabin Pressure) and Jason Hazeley & Joel Morris (Charlie Brooker's Weekly Wipe).

Sam Bain and Jesse Armstrong, who launched Channel 4 sitcom Peep Show with the duo in the same year they started the radio show, also supplied scripts.

Series 5 will be written by the stars alongside many of the show's previous successful and trusted writers, including Mark Evans (Bleak Expectations), Joel Morris & Jason Hazeley (A Touch Of Cloth) and Toby Davies (Yonderland).

Caroline Raphael, Comedy Commissioning Editor for BBC Radio 4, says: "It's always wonderful to see Radio 4 programmes and talent move to television. My parting words to David and Robert were - 'the door is always open' and here they are, back again and we are absolutely delighted, as I am sure the listeners will be."

Mitchell & Webb are currently busy on a number of projects. A ninth series of Channel 4 sitcom Peep Show, in which Mitchell and Webb star as dysfunctional flatmates Mark and Jeremy, is in production, and the duo will also star in Our Men, a new BBC Two comedy drama set in the British embassy of a former soviet country, due to broadcast later this year. Additionally, David Mitchell's new Channel 4 panel show Was It Something I Said? starts early next month.

The new series of That Mitchell & Webb Sound will be broadcast on Radio 4 from Tuesday 26th November in the comedy-flagship 6:30pm slot. The series will be recorded later in the autumn with tickets to the recording (expected to be in very high demand) announced shortly.

Below are a couple of sketches from the radio show set to animation:

And here is one of the best known sketches from That Mitchell And Webb Look. This was first broadcast as a sketch on the radio show.