It was never destined to break box-office records, but over the years The Wicker Man has become the stuff of modern movie mythology. Set on a fictional Scottish island, this dark tale of pagan sacrifice has achieved cult classic status. There is even an annual festival held in its honour.

Now devotees of the offbeat can look forward to more of the same as the film’s director, Robin Hardy, prepares to unveil a follow-up book and a film tie-in, Cowboys for Christ.

The story, which Hardy calls “not quite a sequel”, is set in a small Scottish town called Tressock, where a Christian couple from the US settle to take up work preaching to the enlightened. Hardy addresses some of the same themes from the Wicker Man, including religion, paganism, sex, power and sacrifice, but this time an ancient Borders tradition — the annual common riding in which horsemen patrol the town’s boundaries — plays a central role.

Hardy witnessed a Borders riding five years ago and decided he would like to feature the revered tradition in his next work.

But before his visit to the Borders, Hardy began his research by attending gatherings of Cowboys for Christ, a baptist movement where worshippers wear traditional western dress to praise God and wash away their sins in a trough usually used to store sheep dip. “What I thought rather sweet is the men only take off their 10 gallon hats for the Lord’s Prayer,” says Hardy. “They go back on after the Amen.”

The rootsy culture struck a chord and was the inspiration for his cowboy hero, Steve, and his girlfriend, the pop singer Beth, who bears more than a passing resemblance to all-American teen idols such as Britney Spears. Both are born-again virgins from the American abstinence movement. “They are not bad people. They are sincere Christians, very much part of their pop cowboy culture and utterly innocent,” Hardy explains. “But when they come to Scotland they might as well be in Papua New Guinea. And they are not alerted by strange things that people should be alerted by. And that’s the danger for them.”

The story will be launched in book form at Wigtown festival today, and although there are no firm dates for filming, Christopher Lee and Vanessa Redgrave have signed on for the film, which will be shot in and around Glasgow.

This is Hardy’s first big film project for many years. He has disassociated himself from the current Wicker Man remake, being directed by Neil LaBute and starring Nicholas Cage, saying: “I’m already feeling a sort of schadenfreude because I know what’s in it. Maybe it will turn out to be a good film, but it certainly won’t be The Wicker Man.”

His not-quite-a-sequel is taking up all his time anyway. Hardy says the project has a strong American influence. “American politics are at a particularly interesting stage at the moment because of the strong influence of the religious right,” he says. “America is a country where the political pendulum swings too far before it corrects itself. Think of the McCarthy era, when Arthur Miller wrote The Crucible.”

In the past few years, he says, another witch hunt has begun. “Anyone who disagreed with the war was demonised,” he says. “That’s a trap into which America and unfortunately we in the UK have fallen in the last few years.”

Yet he insists this is no political tract and he doesn’t take sides. “It’s part of the social fabric of our world at the moment and it’s difficult to escape it,” he says.

Now an agnostic, Hardy was raised on a diet of daily chapel attendance while a pupil at various prestigious schools, but claims it didn’t have much effect on him.

However, his interest in religion was piqued by the stories of the King James Bible and the “terrific language and wonderful imagery” spoke to him from a young age.

Born in London in 1939, Hardy’s father died when he was still a baby, and his widowed mother spent her time travelling the world, often taking Hardy and his sister with her because she considered it more interesting than sending them to school. “That lifestyle made me perhaps less settled on a conventional career,” he admits.

It most probably gave him a certain confidence to do what he wanted. He didn’t worry about the backlash that followed The Wicker Man as outraged Scots protested about the fictional depiction of their nation.

And he admits that following the launch of Cowboys for Christ he may even find himself on the wrong end of a tongue-lashing once again from people who might object to his portrayal of the Borders ridings. But if there are complaints, they will stop once the tourists arrive, Hardy believes. The Wicker Man lured visitors to southwest Scotland, where The Wickerman festival is now held in Wigtown.

Hardy is involved in another film-related tourism venture. He is in talks to build a £20m Scottish history theme park with film studio facilities on the site of a former engine factory near Shotts. The wealthy property developers David Kirch and Richard Hayward have already committed some money to the project and Hardy is hoping to enlist their help in raising more.

“Scottish tourism could certainly do with some help,” he says.

“People don’t take their children to Scotland for the bucket and spade, they go for the beauty, castles and history. Many people would love to see something that puts Scotland’s history more in context.”

That’s what’s really keeping him busy at the moment, he confesses, and it keeps the nerves about the book’s reception at bay. “I’ve never wanted just to be a film director,” he says. Watch out — you never know what Robin Hardy could be planning next.

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