More people enjoy being trapped in 'secret chambers'

"It's like, you still want to go for coffee with your friends even if you can talk with them online," she says.

The number of newcomers is mushrooming.

Bai Ge, 26, has done market research of more than 20 such centers in Beijing. His first self-designed room will open by May.

But he believes the market will be saturated soon. "Only the best will survive," he says.

Some center operators concern that the craze will die soon.

Omega Room Escape, for example, believes that re-inventing the themes is the way out.

For its third outlet, the staff is designing simpler rooms for smaller groups of customers, and they are cooperating with a team from Tsinghua University to add hi-tech elements to all the rooms.

To target foreigners, the company is also designing rooms for English-speaking customers.

But Tang of The Lost Ghost Ship believes a classic room is worth retaining, as there will always be new customers.

She says she will keep her rooms as they are, while looking for new venues to open new outlets.

zhangzixuan@chinadaily.com.cn