Award-winning Spanish director Jaime Rosales has sparked huge controversy with his latest film, Bullet In The Head (Tiro En La Cabeza). It follows the everyday life of an ETA member, with no dialogue within earshot and little action until the explosive closing scenes.

During the film's world premiere in competition at the San Sebastian International Film Festival last month, some audience members walked out. Those that stayed were rewarded by a dramatic denouement.

"One of the designers said the film is like a radioactive or nuclear bullet," says Rosales. "There is a sense of anticipation that at any moment it can release a huge charge with a major impact." As director, writer and producer, Rosales says he knew he was making a difficult film. "You have to have patience, work with the film and let it work on you in order to appreciate the point of delivery," he explains.

This bold and challenging approach is one that Rosales has brought to his entire film career. A business school graduate, he decided instead to take his career in an artistic direction by first becoming an opera singer, then a painter, before settling on film-making.

He received a grant to study at the International Film and Television School of San Antonio de los Banos in Cuba. "I wanted to experience a third-world country and to see if the Communist way of life was as the propaganda tries to convince us it is," he explains. "I was a little bit disappointed. There are many billboards in all the streets, but only one that really made sense to me and it said, 'Resistance.'"

He then went on to the Australian Film Television and Radio School in Sydney. "From working in the poorest conditions with rudimentary tools in Cuba to the most modern and high-tech equipment in Sydney was an incredible thing."

However Rosales was drawn back to Spain to tackle subjects closer to home. His debut feature was the 2003 serial-killer drama The Hours Of The Day (Las Horas Del Dia) which screened in the Directors' Fortnight at Cannes, winning the Fipresci prize. With last year's Solitary Fragments (La Soledad), he tackled the Madrid bombings, winning three Goya awards including best director and best film.

Rosales decided to make Bullet In The Head after reading the true story of ETA members who travelled across the border from Spain to France and killed two off-duty policemen in a chance encounter in a roadside cafe.

The film took just two weeks to shoot, mostly in San Sebastian itself. "I said to the producers (Fresdeval Films, Wanda Vision and France's Les Productions Balthazar) that I wanted to begin shooting straight away. They said fine and wrote me a cheque for just under $500,000," Rosales says.

Some of the producers even star in the film, and the lead character, Ion (played by Ion Arretxe), was also the film's art director. Bullet In The Head was released by Wanda Vision on October 3 in Spain, and has taken $30,250 (EUR22,000) to October 12.