SO how does a grown man play a young child on the stage?

For Oswaldtwistle actor Paul Simpson, there was really only one answer -- go back to school.

Paul, who tonight opens in Second From Last In The Sack Race at Bolton's Octagon Theatre, spent a week in the classroom at St Anthony's Primary School at Shadsworth where his wife Donna is a teacher.

"It was great," he said. "I just sat in the middle of all the children and observed them. I could watch how they reacted to things and picked up their mannerisms."

Talking to Paul in a break between rehearsals for the show, he drops a shoulder, turns his head and suddenly the 30-year-old actor is transformed into a young boy, complete with Just William-style short trousers, tank top and knee socks.

"You have got to make the audience believe it is a child in front of them or the play won't work," he said.

Paul plays the key role of Henry Pratt in the play which has been adapted from the novel by David Nobbs.

During the course of the production he plays Henry aged three, five, eight, 11,12, 14 and finally 18.

"It's great fun, but very, very difficult," he said. "This is a wonderfully funny and at times moving play which is just so well written. I really am enjoying it."

Paul is no stranger to the Octagon having played there twice previously, most recently in the Christmas production The Snow Queen.

"I played a child in that too," he said. "It's funny but it seems on stage I play schoolboys and on TV I'm always a car thief, a drug addict or a gay character."

If by now you are wondering where you have heard the name before, Paul has done a lot of TV work including parts in Cold Feet, Queer As Folk and a new series Wine in the Blood.

But it was as an unknown schoolboy that he first hit the headlines.

He was picked from obscurity to take one of the lead roles in a film -- The Nature of the Beast -- shot in and around his home town of Oswaldtwistle.

At the age of 17, Paul was a regular on the Coronation Street set, where he was one of Rita's paperboys.

"I was at Accrington and Rossendale College at the time," he said. "I wasn't an actor at that point and it was very daunting. It nearly put me off acting altogether but Martin Cosgriff who was my drama tutor inspired me to carry on."

After Accrington and Rossendale College Paul studied at the leading drama school Rose Bruford in London where he emerged with a degree in acting.

"I stayed in London for about two years and then I got a northern agent and came home and I've been back ever since," he said.

Since leaving drama school, Paul has found himself very much in demand.

"There is a great deal of difference between TV and theatre work -- and I don't just mean the pay," he laughed.

"With an audience in front of you - and particularly with a play like this one - you really have to engage them. The audience's reaction means so much to actors on the stage.

"If I go to watch a play I always sit bolt upright and give it my full attention because I know what it's like from the other side if you're looking out at people who are only half watching or in some cases clearly not interested."

There seems little danger of lack of interest with Paul's latest Octagon venture.

Second From Last In The Sack Race is the first in a trilogy of novels penned by David Nobbs, the man who created Reginald Perrin and was responsible for the Two Ronnies.

The production involves a lot of music from the period from the Thirties through to the Fifites as young Henry grows up.

"All the scenes are very short which means it's very fast moving and most of the cast play a number of characters about nine or 10 each. I'm the only one who stays as one character throughout," said Paul. "There's a great spirit among the cast and I think this will show in the final production."

By appearing at the Octagon it means Paul can spend as much time as possible with his wife and their young son.

"It's great being so near to home," he said. "I think I've only done one touring production which meant I was away for about 13 or 14 weeks and that was very hard."

And once the production is over what's next for this talented young actor?

"A holiday," he laughs. "Actually for the first time in a long time I haven't got anything definite lined up, but that's the nature of the business."

Somehow I don't think it will be too long before we hear of Paul again.

Second From Last in the Sack Race runs until Saturday, July 6. Details from the Octagon box office on 01204 520661