''Most people in Sichuan opera circles oppose this,'' said Liu Suirong, an official with the Chengdu Sichuan Opera Troupe, speaking above the high-pitched singing of a recent rehearsal in Chengdu's Jin Jiang Theater. ''Face changing is what gives Sichuan opera its unique character, and if Andy Lau uses it somewhere else it will mean nothing.''

This is not the first time Mr. Peng has stirred up Sichuan opera's staid world. In 1998 he caused a scandal by accepting eight girls as students, breaking with the tradition of teaching only men the secret of face changing. Last year he took his act on the road, performing before television cameras for his world-record-setting tour de force -- though there was no previous record registered for him to break.

''If you just stick to the old rules, the art form won't develop,'' Mr. Peng said recently while eating red peppers and noodles in Chengdu.

That kind of behavior upsets more reserved Sichuan opera performers, for whom video cameras are taboo, perhaps rightfully so. A close viewing of Mr. Peng's frenzied world-record performance, which was taped and played repeatedly on Singapore television, reveals bits of colored silk peeking out from the top of his tunic, behind which the masks evidently disappear.

It is also clear from the video that the masks are yanked from Mr. Peng's face with a system of black strings that would never be seen in the gloom of a theater.

Face changing got its start 300 years ago, when Sichuan opera actors began changing the color of their faces during performances by blowing into a bowl of red, black or gold powder, which would adhere to their oiled skin. In another method, actors would smear their faces with colored paste concealed in the palms of their hands.

By the 1920's, opera masters began using layers of masks made of oiled paper or dried pig bladders, which they could peel one after another in the blink of an eye. Mr. Peng takes credit for developing the full-face, painted silk masks used today. They can be worn in layers, as much as two dozen thick, and be pulled off one by one.