After cancelling three previews due to technical difficulties, the National Theatre this weekend postponed the opening of its much-anticipated adaptation of Philip Pullman's His Dark Materials. Nicholas Wright's two-part stage version of Pullman's award-winning children's book trilogy was due to receive its world premiere at the NT Olivier on Saturday 20 December 2003, but the press day performances have now been rescheduled for Saturday 3 January 2004.

NT artistic director Nicholas Hytner, who's also directing the productions, said: "When I took this on, I thought it was unstageable. Now I know that we can do it - but we need more time to get this hugely ambitious production right. With hindsight, I should have scheduled more time. We have had to cancel the first previews of both parts. I apologise unreservedly to the people we've had to turn away. We're scheduling extra performances to accommodate those people."

Last week, the first two previews of Part I (on 4 and 5 December) were cancelled when technical difficulties were encountered during final rehearsals, and the first preview of Part II (13 December) has been delayed by one evening. Though new dates have not yet been announced, the National plans to schedule extra performances for people who would otherwise be unable to get into the sold-out run, which is currently due to conclude on 20 March 2004.

His Dark Materials is a coming of age and a transforming spiritual experience for Lyra and Will (played by Anna Maxwell Martin and Dominic Cooper). Their great quest demands a savage struggle against the most dangerous of enemies. They encounter fantastical creatures in parallel worlds - rebellious angels, soul-eating spectres, child-catching Gobblers and the armoured bears and witch-clans of the Arctic. Finally, before reaching, perhaps, the republic of heaven, they must visit the land of the dead.

The cast also includes former 007 Timothy Dalton, Niamh Cusack and Patricia Hodge as well as Samuel Barnett, John Carlisle, Patrick Godfrey, Stephen Greif, Jamie Harding, Akbar Khurta, Inika Leigh Wright, Helen Lymbery, Tim McMullan, Helen Murton, Cecilia Noble, Nick Sampson, Danny Sapani, Jason Thorpe, Russell Tovey, Ben Whishaw, Ben Wright and Richard Youman.

Philip Pullman's original trilogy comprises Northern Lights, The Subtle Knife and The Amber Spyglass. In addition to other awards, the last title in the series won both the Whitbread Children's Book of the Year and Whitbread Book of the Year, the first children's book to win the main prize in the award's history.

According to NT promotional material, the theatrical version "will be an epic production both in its narrative scope and its staging, involving artists from new technologies as well as old, and aims to create an experience as meaningful for 12-year-olds as for adults." It's designed by Giles Cadle with costumes by Jon Morrell, puppets by Michael Curry, lighting by Paule Constable, choreography by Aletta Collins, music by Jonathan Dove, fights by Terry King and sound by Paul Groothuis.

- by Terri Paddock