By Michael Hubbard BBC News

Cult indie band Belle and Sebastian have undergone a lot of change in recent months.

We certainly don't have an idea of what the group's about

Stuart Murdoch

They have just released the soundtrack to the film Storytelling, their first album for a movie, and their cellist and vocalist, Isobel Campbell, left the band in the middle of their tour of the United States.

The Scottish band's lynchpin, Stuart Murdoch, said Campbell's departure was not entirely unexpected.

"She came out to do the American tour a week late," he comments.

"She wanted just to do a couple of weeks of the three-week tour, but apparently a week was long enough, so she went home."

Murdoch said that the band had not been her priority for a couple of years.

Departure

"I think she was much more interested in her solo career," he explains.

Campbell, now with The Gentle Waves, was perhaps the most visible member of the band aside from Murdoch.

How did the band deal with her departure?

"We dealt with it quite a long time ago," says Murdoch. "She was an integral part of the group, but she hasn't been for a couple of years."

He confirms the band and Campbell are still on speaking terms.

Core

"There's no animosity there, more... a shrug of resignation."

And there are apparently no plans afoot to replace her, leaving a core of seven members in the band.

Belle and Sebastian, named after a French television series about a boy and his dog, was formed in an all-night caf� in Glasgow in 1996 by Stuart Murdoch (guitar/vocals) and Stuart David (bass), who met on a government training scheme.

As the group became a group it became more of an adventure

Stuart Murdoch

The band recorded their debut album Tigermilk in three days and released it as a limited edition of 1,000 copies.

The 60s pop meets folk-rock sound of the band continued with the release of four more albums, spawning two top 40 singles along the way.

David left the band in late 2000, leaving one original member.

Meanwhile, a new album has been released. For a band so resolutely independent, entering the commercial world of moviemaking seemed to some fans a peculiar decision.

"We certainly don't have an idea of what the group's about, so we do what we feel like and let other people think," counters Murdoch.

The band flew to New York to see the film at the request of the director, Todd Solondz.

Oddity

"When we first saw it, it was a rambling two-and-a-half hour thing in two parts and we couldn't really understand where the two parts came together," Murdoch recalls.

"I don't think the director could either, but we still liked the film a lot. Over time, about an hour of the film was cut. We knew as we were working how much of our music he would use."

In the end, very little was, making the "soundtrack album" that is Storytelling something of an oddity.

It consists of portions of music written for the film plus significant amounts of music that was developed by the band afterwards, begging the question - should we see the film before listening to the CD?

Murdoch believes it doesn't matter.

'Concern'

"We had to start recording again after we'd done the music for the film to develop these little themes that we had. Some of them are in the film and some of them are not.

Isobel Campbell is pursuing a solo career

"We went back to the studio, much to the concern of our label, Jeepster," he continues, "but you've got to do these things sometimes."

Murdoch then suggested the label was "finished" and that the band's next album will be for a different label, although he avoided saying which one.

Jeepster, however, has said it had advised the band to begin negotiations with other labels in January.

Slimmed-down

What does the future hold for Belle and Sebastian, slimmed down and on a new label?

On whether or not the slimmed-down band would consider doing more soundtracks at least, Murdoch is unequivocal.

"We've got our heads in the '60s too much when it comes to soundtracks. I think we'd leave soundtracks for a while," he says. Murdoch believes that the band's debut album remains its best to date.

"We've sort of been unravelling since then - it was all kind of new after that. As the group became a group it became more of an adventure.

"I suppose what I think is that every record becomes better, but there are more imperfections in each record too. It's hard to explain."

Murdoch intends to begin assembling ideas with the remaining six band members in the summer of this year for a new album, expected out early next year.

Storytelling by Belle and Sebastian is out now on Jeepster Records.