NOVELIST Kate Atkinson had no objection when York Theatre Royal artistic director Damian Cruden sought permission to stage the world premiere adaptation of Behind The Scenes At The Museum.

Her 1995 novel, winner of the Whitbread Book Of The Year, is set in York, more precisely above a pet shop near the Minster, where Ruby Lennox relates the story of her family from the end of the 19th century onwards.

"If anyone should put it on first, then it should be the Theatre Royal. It makes perfect sense to me," says Kate, who was born in York and now lives in Edinburgh.

This year Kate may have written her first full-length stage play, Abandonment - which played to full houses at the Traverse Theatre during the Edinburgh Festival - but she has not adapted her novel for the Theatre Royal. Why? Partly because she is writing the television adaptation; partly because she was pleased by the choice of Bryony Lavery, who had done this summer's radio adaptation for BBC Radio 4.

"I think it would have been an horrendous idea for me to do it," she says, her light-hearted thought accompanied by a laugh. "I've written only one long play, and Bryony is such a good playwright and so experienced - and I know she really likes the book."

Kate attended the first read-through a year ago, and made a few suggestions but she has left Bryony to her own devices. "I thought the right thing was to let Bryony write it, because I don't want to put my sixpenn'orth in when I think she knows more than me about writing plays," she reasons.

Having written the first chapter for Behind The Scenes At The Museum as long ago as 1990, and written two more novels and other writings since 1995, Kate does not feel protective about her characters.

"I've gone beyond that. I've released them; I look to the next book. The story is out there, it's strong and it has a life of its own," she says. "If a favourite scene goes for the play, fair enough. You just have to be ruthless about it."

No doubt those sentiments will be music to the ears of Bryony Lavery.

"Kate, Damian and I were adamant that all the strands of the novel should be there. In a two-and-a-half-hour show, we have to go very quickly through the novel and I think we have the essence of pretty much everything that's in the book," she says. "But inevitably certain things have had to go, so this is the dieting version!"

Bryony says the characters are so strong that they leap off the page on to the stage: "They are very clear and original, and everything you need is in the novel. Of course Kate may storm up to me on the first night and say 'How could you do this?', but the way I feel when adapting a book is 'Oh, good. I've got someone who's already written the characters and settings, and it's just my job to serve them'."

Behind The Scenes At The Museum, York Theatre Royal, October 26 to November 18. Tickets cost from £7; ring 01904 623568.