The Wicker Man: The pagan players are ready to set the stage on fire

A new play based on The Wicker Man features a novel take on the cult film

There are certain roles so associated with a single actor that they just aren't worth trying to make your own - and Greg Hemphill knows it. "If somebody had come to me and said, 'We'd like you to be Lord Summerisle in our production of The Wicker Man, I'd have told them I thought they were barking up the wrong tree," says the actor best known for his cult Scottish television comedy two-handers, Chewin' the Fat and Still Game.

Still, he has managed to find an ingenious way to take on the role made famous by Christopher Lee in Robin Hardy's cult 1973 film. "I'm playing an amateur actor with ideas above his station who wants to play Summerisle, so I feel like I'm protected against accusations of not being as good as Christopher Lee. It's my safety net."

In many respects, An Appointment with The Wicker Man, this spring's flagship new production from the National Theatre of Scotland, is what you might call a non-remake: part re-tread, part homage, part meta-spoof. In this version, scripted by Hemphill and Donald McLeary and directed by the NTS' artistic director Vicky Featherstone, the mainlander sent to a strange Scottish island isn't the virginal policeman Sergeant Howie (played by Edward Woodward in the film). Instead, it's an actor who plays a policeman on television, who's been hired to star in an am-dram version of The Wicker Man after the mysterious disappearance of the original principal. Harry Potter alumnus Sean Biggerstaff plays this new lead, whose strait-laced professionalism chafes against the free-spirited amateurism of his provincial new colleagues.

"We knew that just restaging the film would be undramatic for the audience," says Hemphill. "So we decided to take it in a different direction, to see if we could celebrate the film by producing something with the same beats and the same iconography, but which is its own story." Featherstone, who conceived the project, says the staging of the film's famous scenes "isn't how I would re-create them, it's how an amateur theatre company who love the film would." She won't be drawn on how that relates to the climactic burning of the Wicker Man scene, though.

"We set off on this project with the agreement that we wouldn't make fun of the film, but that we might well make fun of this fictional group and their attempts to interpret it," says Hemphill.

As far as Featherstone's aware, The Wicker Man hasn't been adapted for the stage before, and she views the original's cult cachet as an opportunity to attract "an audience who go to films, to see comedy, to gigs, but who don't see themselves as theatregoers."

Hemphill has analysed The Wicker Man and figured out what makes it tick. "People say the film terrified them," he says, "but I think their memory must be playing a trick on them. It doesn't have any of those horror beats we're used to, it doesn't have chainsaw-wielding madmen or cats leaping in front of the camera, or blood or gore. Even the ending is disturbing rather than terrifying, so it horrifies you without any real scares. It's an amazing achievement, when you think about it."

What it does have going for it, he says, is a creeping sense of otherness for metropolitan viewers unused to the notion of wilderness, and an all-pervading sexuality that's often forgotten about. "It's all about Sergeant Howie feeling like a cork drifting in this ocean of wanton paganism, that's the real driving force of the film." Has that transferred to the stage? "Possibly," he laughs. "There has to be a sense of bawdiness, because that's what's in the original film."

'An Appointment with The Wicker Man', MacRobert Arts Centre, Stirling (01786 466666) Friday & Saturday; then touring (nationaltheatrescotland.com)