Preview: Clint Eastwood surprises again with Hereafter, a film that explores the shady side of death

ALMOST every autumn lately, it seems, Clint Eastwood drops a little surprise on the moviegoing public: an unheralded, modestly budgeted film about a subject that hardly seems to fit the Eastwood mould.

In 2004 there was Million Dollar Baby, about a female boxer; in 2008 there was Gran Torino, about a bigoted Korean War vet, played by Eastwood himself, who forms an unlikely, heartwarming friendship with a young Hmong boy.

His latest film, Hereafter, which has just opened in the US and comes to the UK at the beginning of next year, ventures into supernatural territory, which is about the last place you would expect to find Eastwood. Hereafter concerns itself with just what the title suggests: what we can look forward to after we die.

Eastwood is 80 now, and his film immortality, as both an actor and a director, is assured. He has never seemed remotely spiritual.

His trademark characters – Dirty Harry and the Man with No Name, and even Walt Kowalksi, the Gran Torino vet – all face death squarely and unflinchingly, without a lot of hand-wringing about what happens on the other side. Hereafter, though, weaves together the stories of three people who have death on their minds pretty much all the time: a French journalist (Cecile de France) who has a near-death experience during the 2004 tsunami; a reluctant psychic (Matt Damon) who has visions of the afterlife; and a London schoolboy (Frankie McLaren) who is desperate to get in touch with his dead twin brother. They all meet, and their stories connect, at the London Book Fair, of all places. No-one gets shot, no blows are exchanged.

Has Eastwood, famously flinty and cold-eyed, at long last gone squishy? "Everyone has had these thoughts pass across his mind once in a while," he says.

"Is there an afterlife? What's it like? All the great religions have tried to deal with these questions."

He adds that what he liked about the script was that "it has a spiritual feeling without any particular religious touch."

But mostly what appealed to him was the storytelling. "I liked the way the script took contemporary events like the tsunami and the London terrorist bombings and used them in a story that tapped into a general curiosity about the hereafter and whether it exists," he says. "I liked the way the three tales all converged. That's something I had never tried before. And the reticent hero is always interesting, the hero who doesn't appreciate the gift he has."

Hereafter was written by Peter Morgan, better known for his films about royalty – The Queen, The Other Boleyn Girl – and for his play Frost/Nixon, which he later turned into a movie. His involvement in a project about the afterlife is in many ways even more remarkable than Eastwood's, and his script, as it happens, underwent a near-death experience and then a resurrection.

What prompted Hereafter, he says, was the book If the Spirit Moves You: Life and Love After Death, by Justine Picardie, a British journalist devastated by the premature death of her sister, Ruth.

For that book, which is at once hopeful and sceptical, Picardie visited spiritualists, mediums and people who claimed to be able to record the voices of the dead. "I was just gripped by it," Morgan says. "It made me realise we know so much of life before birth, and so little about life after death."

Morgan began writing a screenplay without any clear idea of where it was going. "So much of what I usually do offers solution or explanations, but this time I wanted to write something open-ended," he says. "I didn't want answers. I wanted to ask questions."

He put the script away for a while, but after a close friend died unexpectedly, he picked it up again.

"That really startled me," he says of his friend's death. "In the church I kept thinking, 'Now what? Where? What's happened?"'

Hoping just for a reaction, Morgan passed the script to his agent, who instead sent it off to the producer Kathleen Kennedy (The Curious Case of Benjamin Button, Jurassic Park). Seeing a resemblance to The Sixth Sense, Kennedy, in turn, showed the script to the director of that film, M Night Shyamalan. Later, she happened to be on the soundstage of Indiana Jones and the Kingdom of the Crystal Skull while talking to Shyamalan on the phone, and she was overheard by Steven Spielberg, who, according to Morgan, said, "I like the sound of that."

He liked the sound of it so much that he read the screenplay and made extensive notes, which Morgan immediately addressed in a revision.

But Spielberg thought the revision was not as "humble" or "pure" as the original, Morgan says. "He told me, 'I think I've ruined your screenplay.' Then he said, 'Can I show it to my friend Clint?"' A couple of months later he was bewildered when he learned Eastwood, who had purchased the rights to Hereafter, was already filming off the original script. Though known for writing on spec and resisting the traditional development process, Morgan had been looking forward to working with Eastwood.

"I imagined we'd have all sorts of conversations about the characters, about the plot," he says. "But we never did.

"What you see on the screen is this thing I wrote very sketchily in the mountains of Austria."

Eastwood says he typically works this way.

"I believe very strongly in first impressions," he explains. "When something hits you and excites your interest, there's really no reason to kill it with improvements."