Open House experience plumbs the depths of art

At 9:41 on a recent Sunday morning, the text message was sent: "Come to Fangyuan Xi Lu. Right of the Sunny Golden Market. Left of the U&D Jewelry. Underground 20A near Sculpting in Time Cafe. Call for assistance. Time: 2 to 6 pm."

The recipients of the message arrived one by one, sometimes in pairs or a few groups of three or so. They were led down stairs, through a maze of dimly lit corridors deep below Beijing's busy streets.

There they found a system of subterranean life unknown to most people who live in the city. Clotheslines, scattered shoes and small rooms rented by workers are evidence of a people who cannot afford to live on the surface - waiters, maids, security guards.