The cult status accorded to the British horror film The Wicker Man has always surprised me. When I first saw it — indeed when I last saw it — on its release in 1973 the antics it depicted among isolated island folk in Scotland seemed more funny than frightening. Like much else in that era of sexploitation, though, it featured a phwoar-worthy array of crumpet, including Britt Ekland, who was in between romantic stints with Peter Sellers and Rod Stewart, and Ingrid Pitt, better known for her work as a screen vampire at the time — as was the film’s star, Christopher Lee.

Yet cult status the movie certainly enjoys — to the extent of prompting sing-along screenings in similar style to those given of The Sound of Music and Grease. There is one tomorrow at the Ultimate Picture Palace, which my colleague Tim Hughes describes today in Weekend.

I wondered at first if there was sufficient music to sing along to. But a faded cutting from our library file put me right. The critic noted amusingly: “The sophistication of the direction [by Robin Hardy, who is coming tomorrow] has been taken too far in the treatment of the many songs which are put over with a professional expertise that suggests that the islanders spend all their spare time rehearsing for gigs at the Festival Hall.”

As the status of the film has grown over the decades, so has knowledge of the role played in its conception by the writer (and former actor) David Pinner. This was understood by me in outline, almost from the first, he being someone I came to know as a schoolboy. In 1966 — during one of those pauses that punctuate an actor’s life — he returned to his old school in Peterborough to assist in a production of Macbeth. Aged 14, I played the tyrant’s principal lieutenant, Seyton, and one of the three murderers.

The Wikipedia entry on Pinner’s novel Ritual — in which a devout Christian policeman is called to investigate what appears to be the ritual murder of a young girl in a rural village — makes clear its importance in the conception of The Wicker Man and is worth quoting at length. The detail came from interviews with the author. By a curious coincidence, the story touches on Agatha Christie’s The Mousetrap, which is playing in Oxford this week.

It reads: “When Pinner was 26, he had just written the vampire comedy [play] Fanghorn, and was playing the lead role of Sergeant Trotter in . . . The Mousetrap in the West End. He decided to write a film treatment that dealt with the occult (like Fanghorn) but which was also a detective story (like The Mousetrap). Film director Michael Winner liked Pinner’s treatment, and considered making it his next film, with John Hurt in mind for the lead role. However, Winner deemed the treatment to be “too full of imagery”, and Pinner’s agent, Jonathan Clowes, felt that Winner might sit on the project for a long time. The collaboration came to a halt.

“Clowes suggested that Pinner instead expand Ritual into a novel, promising that he would get it published. Pinner wrote it in seven weeks, while he was still acting in The Mousetrap. He would write sections of the novel on the tube train on his way into the West End, and even on his dressing room floor. While driving to his agent’s office with the only completed copy of Ritual in existence, Pinner accidentally left the manuscript on the roof of the car; it would most likely have fallen off and been lost forever if another driver had not got Pinner’s attention and alerted him to his mistake.”

Besides the stars already mentioned, the film featured Edward Woodward in the key role of the investigating policeman, Sgt Neil Howie. Up until that point Woodward’s chief claims to fame had been as TV detective Callan and for his work on the stage.

In the winter of 1970/71 he was in a series of productions at the Old Vic in a cast which today seems impossibly stellar. It included Sarah Badel, Anna Carteret, Tom Baker, Jeremy Brett, Jim Dale, Derek Jacobi, Joan Plowright, Maggie Smith, Robert Stephens, Jane Lapotaire, Geraldine McEwan and Coral Browne.

The last, a celebrated wit, remarked on first hearing the name of her co-star: “Edward Woodward: sounds like a fart in the bath.” Which, of course, it does.

At the time of Woodward’s death four years ago, I recalled his work at Oxford Playhouse and wrote: “I feel privileged to have seen him there in September 1973 in the British premiere of Ferenc Molnar’s comedy The Wolf, in which he starred with Judi Dench and Leo McKern. The play was a highlight of the Meadow Players’ last season at the theatre, under the director Frank Hauser. It later triumphed in the West End. “Nearly 30 years later, in October 2002, I saw him at the Playhouse again in what was destined to be his last stage role, in Leonard Preston’s Goodbye Gilbert Harding. He gave a marvellous portrayal of this irascible — and very sad — early icon of the TV age.”