The stage version of the sprawling work recently began performances at London's Royal National Theatre, directed by Nicholas Hytner as a two-part epic. The story spans many universes and calls for flying balloons, witches, demons, magic and even armored bears. Hytner canceled two previews of Part One, and has moved the first preview of Part Two from Dec.13 to Dec. 15. The Dec. 20 press night has been spirited to Jan. 3.

Pullman reportedly turned down an invitation to adapt his own work for the screen. Pullman said that after spending seven years with the trilogy, "the last thing I want to do is take it apart and put it together again."

"His Dark Materials" is comprised of the volumes "The Golden Compass," "The Subtle Knife" and "The Amber Spyglass." The books have been translated into 37 foreign languages.

The fantasies center on a precocious child called Lyra Belacqua, or, at other times, Lyra Silvertongue. She lives around the grounds of Oxford's Jordan College, her ambitious parents busy elsewhere. The story features such mystical elements as Dust, a secret substance; creatures called "gyptians"; a knife that can slice its way into parallel worlds; a couple of rebels in the persons of Lord Asriel and Mrs. Coulter; and a device called an alethiometer, which divines the truth.

New Line also produced the "Lord of the Rings" fantasy trilogy.