Notting Hill director Roger Michell's latest film, Enduring Love, has been adapted from Ian McEwan's best-seller and is released in the US on Friday.
By Victoria Lindrea
BBC News entertainment reporter
"It's a thriller about love, that's how I like to bill it," says Mr Michell of his new movie, which tells the story of a couple whose lives interlock with an obsessive stranger.
Roger Michell (centre) cast actors Daniel Craig (left) and Rhys Ifans
Road to Perdition and Sylvia star Daniel Craig plays Joe, a philosophy lecturer who becomes the object of desire for loner Jed (Rhys Ifans) after the pair witness a tragic ballooning accident.
Jed follows Joe to his home in north London, where he begins watching his house and threatening his girlfriend Claire.
It is essentially a stalker movie - fraught with tension and menace - and the ambiguity of the Jed character is central to the film. Is he in love with Joe? Is he malevolent, benign or sick?
"To a certain extent, it's an extended meditation on different types of love and different types of relationship, whether love endures - and what it's like to endure being loved," explains Mr Michell.
Booker winner Ian McEwan, whose novel has more thematic complexity than the film, had strong objections to early drafts of the screenplay.
"We tried to accommodate his anxieties as much as we could, without destroying what we were trying to do," says Mr Michell, whose other films include Changing Lanes and The Mother.
"But it wasn't until he saw a rush [early version] of the film that I think he got what we were trying to do. Since then, he's been very supportive of the film."
Ifans also worked with Roger Michell on Notting Hill
Mr Michell took on the adaptation with screenwriter Joe Penhall - and had to make a number of changes.
"As with all high-concept stories adapted for cinema, your first duty is to make the screenplay feel real," he says.
"I think there are lots of things that work fine in the book that turn into a dilemma in the cinema.
"All the characters are different in the film," he explains. "In the book, Jed inherits a lot of money from his dead mother, lives in a large house in Hampstead and wears bright red trainers."
"That all works very well in a novel, but it seemed to me unlikely that I would be able to sell the notion of this guy being real on film."
Among the novel's most pivotal images is the balloon accident that triggers Jed's delusions.
"The balloon was the biggest challenge," says Mr Michell, who spent several weeks in the windswept Chiltern Hills co-ordinating the shoot.
Oscar-nominated Samantha Morton plays Joe's girlfriend, Claire
"Everyone said it was their favourite opening of any novel they've ever read," he says.
But he adds: "It is a drag when everybody knows the book - the last thing you want to hear was 'oh, it's my favourite book'."
It is a situation Roger Michell understands only too well - he was the original director on Captain Corelli's Mandolin, but had to drop out after a heart attack.
John Madden replaced him - and it proved a critical failure. But Mr Michell generously concedes Mr Madden was under a host of commercial pressures.
"If you go to America, you are making films for $70m (£40m) plus, then you expect to have to listen to various people's opinions on how you should make a film."
"But if you are making a small film, part of the advantage of that is not having to listen to other people," he says.
Enduring Love could so easily have gone a different way. The story was originally bought by Sony and the screenplay relocated to Boston with Shine director Scott Hicks.
Filming took place in Mr Michell's north London neighbourhood
When that project fell through, current producer Kevin Loader snapped up the rights.
Mr Michell himself succumbed to studio pressure to alter the ending of Changing Lanes, the 2002 drama starring Ben Affleck and Samuel L Jackson.
But it is a film he remains proud of, despite the changes.
"I think this film, bizarrely, is quite similar to Changing Lanes," he says. "It's about two men who meet by chance, and as a result of an accident, both their lives spin out of control.
"I think there are thematic links between my films, though obviously you are trying not to make the same film over and over again," he adds.
"I don't think about film-making strategically. I make films for me and my friends to watch."
Enduring Love opens in the US on 29 October and the UK on 26 November.