Rather unusually for my movies, it does have a beginning and an end,' Nicolas Roeg says as an introduction of his new feature Puffball at the Galway Film Fleadh in July.

That is not to say the 79-year-old director, who made his mark with challenging films including Don't Look Now, Bad Timing and The Man Who Fell To Earth, has gone mainstream. Puffball is an unusual story about supernatural forces unleashed when a young woman falls pregnant in a mysterious valley with some peculiar neighbours.

Roeg knows the film will not please everyone. He asks, 'Was it Orson Welles who said one thing there's no shortage of in the movie business is opinion'' - but he says it is 'fantastic' how only five or six people walked out of the film's 1,000-person world premiere at the Transilvania International Film Festival.

The movie is a long-gestating project for Tall Stories Films producer Dan Weldon, who also wrote the script based on his mother Fay's novel of the same name. Roeg was excited to take it on after reading the script. 'Fay is a very special English writer. She touches things hidden inside,' Roeg says in Galway. 'With this story, I had a sense less of plot than of truth of life, and I wanted to inhabit that properly. There are only 38 dramatic situations, it's the inhabitants of those that make it interesting.'

Mrs Henderson Presents star Kelly Reilly came on board for the lead and was joined by Miranda Richardson, Rita Tushingham and Roeg's former Don't Look Now star Donald Sutherland.

Sutherland has limited screen time but was pivotal, Roeg says. 'It's a difficult part to play because he doesn't go through a physical transformation, it's an attitude change,' the director says. 'He stamped into it, he stamped right inside the film, it's not just some guest appearance.'

In addition to Tall Stories, the producers were Montreal-based Amerique, the UK's Dan Films and Ireland's Grand Pictures. Backers include the UK Film Council's New Cinema Fund (which put in $1.2m), the Irish Film Board and Northern Ireland Screen. Wild Bunch is handling international sales and has sold a number of territories already. Puffball will have its North American premiere at the Montreal World Film Festival (see p19).

Roeg shot the film in 2006 for six weeks in Ireland and Northern Ireland. 'It's not a genre of anything, or it's the genre of everything,' Roeg says of the hard-to-pin-down final product. 'It has jealousy, hope, ambition, sex, lies - a bit like our lives.'

Roeg will not discuss future projects, but plans to keep making films: 'How do you stop' I'd have to have my skull emptied.'