New film enters the private world of Pete and Dud, the warring kings of British satire

Cook's life, including his anarchic and often foul-mouthed routines with Moore, becomes a story in its own right

Rhys Ifans, the actor best known for his portrayal of Hugh Grant's slob flatmate in the movie Notting Hill, will play Peter Cook in a "warts and all" Channel 4 film about his up-and-down relationship with fellow comedian Dudley Moore.

Not Only ... But Always explores the pair's life together - from their first meeting in the 1960s to Cook's death in early 1995, aged 58. Their often tempestuous partnership has been condensed into just two hours, and chronicles the pivotal moments in their careers.

Moore, the diminutive "sex thimble" who died nearly two years ago at the age of 66 from complications arising from a degenerative illness, will be played by the little-known Aidan McArdle, who has worked mainly on the stage. Ifans is the Welsh star who promised much in Notting Hill but has failed to find his stride after starring in a series of flops such as Rancid Aluminium and Love, Honour and Obey.

Cook and Moore helped to redefine British comedy with their anarchic wit and often foul-mouthed performances playing characters such as Derek and Clive.

Their work with Alan Bennett and Jonathan Miller in their Beyond The Fringe review made them the top figures in British satire, and Cook was also one of the founders of Private Eye magazine, while Moore went on to become one of Hollywood's biggest stars.

Channel 4 is funding the film as part of its new emphasis on drama, which the head of programmes, Kevin Lygo, said would help the station to "make a mark".

It is being made by Company Pictures, which backed the successful series Shameless.

The writer and director of Not Only ... But Always, Terry Johnson, was behind the Olivier Award-winning National Theatre show Cleo, Camping, Emmanuelle and Dick about the romance between Carry On stars Sid James and Barbara Windsor. It was later adapted for television and screened by ITV as Cor, Blimey!

Johnson - a huge fan of Cook and Moore - was also responsible for the stage hit Hitchcock Blonde, starring Bond girl Rosamund Pike.

The executive producer of the film, Charlie Pattinson, said: "The thing about Terry is that he loves his characters. This is not a whitewash, but it's an extremely affectionate and tender portrait although it is 'warts and all'. I would really hope we don't upset anyone. Terry regards them both as greats of British comedy."

The Beyond The Fringe team found huge success on both sides of the Atlantic before Cook and Moore set out as a duo, establishing their "Pete and Dud" routines in which they appeared as cloth-capped Londoners who sat for hours discussing the meaning of life in deadpan po-faced style, which featured in their BBC series Not Only ... But Also.

Although they went on to work solo, the hedonistic pair would reunite occasionally for their filthy Derek and Clive dialogues.

But towards the end of their partnership, their close association had largely broken down, with Cook, who died of an intestinal haemorrhage, often cruelly mocking Moore.

Pattinson said of the film: "Predominantly it is Peter's story, but the emotional spin on the story is the relationship between Peter and Dudley, which has that sort of 'every relationship' quality to it whether you knew who they were or not. It's a marriage that explodes then comes back together and then explodes again.

"It uses markers from their creative life to tell the story, such as Beyond The Fringe, Not Only ... But Also, and it touches on Dudley's film career and Peter's less successful years."

Filming begins a week on Wednesday and will take place almost entirely in New Zealand, which will double for locations as diverse as Cambridge, New York, Los Angeles, where Moore made his home, the Caribbean, where they wrote together, and Exmoor.

Channel 4's head of drama, John Yorke, said: "It's a history of British comedy, a look at the psychology of a relationship and a portrait of post-war Britain - but most of all it's the story of Pete and Dud."