by Caroline Briggs
BBC News entertainment reporter
Actor Aidan McArdle stars in the TV drama Not Only But Always as Dudley Moore. He explains what it was like stepping into the shoes of a legend, alongside Rhys Ifans as Peter Cook.
Rhys Ifans (l) stars alongside Aidan McArdle
Peter Cook and Dudley Moore were a perfect double-act - the tall, elegant, quick-witted Cook contrasting with the short and intensely dark Moore.
But the comedy duo, who were credited as the inventors of modern British satire, shared a complex relationship and each had deeply troubled private lives.
Not Only But Always, written by acclaimed playwright Terry Johnson, explores Cook and Moore's creative collaborations and personal resentments, starting with their first meeting as Oxbridge graduates in 1959.
It takes viewers through their beginnings in Beyond The Fringe, Pete and Dud, Derek and Clive, to Cook's founding of Private Eye magazine and Moore's transformation into a Hollywood star.
It ends with Cook's death at the age of 57 in 1995.
Stage and television actor Aidan McArdle portrays Moore alongside Rhys Ifans as the irrepressible Cook.
McArdle says he enjoyed the challenge of playing Moore, who died of a rare brain condition in March 2002.
"The original casting director had laughed at the thought of me, and Irishman, playing Dudley Moore but when the casting agent changed, they decided to give me a go," he says.
"I got as many videos and DVDs of his stuff as I could and I just sat in front of the television."
For the audition, McArdle was asked to recreate one of Moore's performances with the writer, Terry Johnson, as Cook.
"It was really difficult and very strange trying to recreate a performance, complete with laughing," he explains.
Cook and Moore's series Not Only... But Also was a huge hit
"At one point I was not going to go into the audition as I was appalling, but after some practice it just clicked."
Ifans, who has starred in a number of films including Notting Hill and Enduring Love, was chased for two years before agreeing to play Cook.
He said he was "dying to do it", but frightened at finding the right Dudley to make the film work.
McArdle says it was "great fun" working with Ifans, with each taking on their roles away from the camera too.
"We both started taking on our roles: I started playing the slightly overbearing perfectionist and he became a bit of a bully," says McArdle.
"I think Rhys had a secret competition with himself to see if he could make me choke with laughter every day.
"He would wait until I was drinking something and then say something that would make me breathe in, spit out or spray the contents of the liquid in question."
McArdle describes Cook and Moore's co-dependent working relationship as a "marriage".
"Their relationship had similar attributes to that of a marriage. They needed each other, but they also disliked the fact that they needed each other.
"There is a part in the film where Peter Cook looks at Dudley and says 'to the death then'.
"There is an element that they were thrown together but could not leave each other's shadow."
Moore went on to pursue a successful career in Hollywood in the 1970s starring in a number of hit screen comedies.
He played alongside Bo Derek in the movie 10 in 1979 and his role as a hard-drinking millionaire in the 1981 film Arthur then won him an Oscar nomination.
McArdle admits that portraying a legend was a daunting experience.
"Playing Dudley was scary because he was so well loved," he says.
"If you get it wrong it is glaringly obvious. Everyone who has seen even just one film with Dudley in it will know.
"It was a great responsibility to do it properly and to do it with sensitivity."
Not Only But Always is on Channel 4 at 2100 GMT on 30 December.