"You'll never sleep well again."

Actor Lamar Staton plays a frozen man in the Ice Chamber

That's the tag line for Nightmare, a sophisticated haunted house "theatre" created by Psycho Clan, four producers working with a group of young visual and theatre artists. It offers 13 high-tech rooms of terror. (No one under 16 admitted. Not recommended for those with heart problems, or anyone prone to seizures or afflicted with clinical anxiety. And once you're in, you can't leave.)

The 30-minute nightmare experience is staged on a 9,000-square-foot floor at the Clemente Soto Velez Cultural Center on Manhattan's Lower East Side. Small groups go through in three-minute intervals. Runs through October 31.