密室逃脱 (mìshì táotuō, escape room) has become hugely popular in China, with thousands of venues in major cities. The variety show 密室大逃脱 (Great Escape) further boosted the trend.
usage
密室 can refer to a literal hidden room or to the escape room entertainment genre. In mystery fiction, 密室杀人 (mìshì shārén) means a 'locked-room murder.'