People who knew Tang Yongming say they never imagined he could do such a horrible, senseless thing. A few minutes after noon on Aug. 9, just 12 hours after the start of the 2008 Olympics, Tang, 47, savagely knifed a visiting American couple inside Beijing's 13th-century Drum Tower. Then he jumped 130 feet to his death from the ancient landmark's western balcony. Minneapolis businessman Todd Bachman--father-in-law of U.S. men's indoor-volleyball coach Hugh McCutcheon--died of stab wounds. Bachman's wife, Barbara, survived, despite life-threatening injuries. Their guide, a young Chinese woman, was also hurt, although less seriously. Tang remains an enigma. "There was nothing abnormal about him, absolutely nothing," says Wang Yongxian, a prim, businesslike community worker who tried to help Tang find a new job five years ago, after his previous employer let him go. Wang's colleague Xu Guofang agrees: "He wasn't just 'relatively' ordinary. He was simply ordinary. Period."

Back in August, Tang's ordinariness was cause for relief: authorities quickly figured out that he wasn't a terrorist, and the Games went on. But the truth is perhaps more disturbing. The troubles that destroyed Tang--the loss of his job, the collapse of his marriage, heartbreak over his wastrel only child--are all too common across China.

The country is the world's most stressful: three decades of reforms have shredded China's safety net and transformed society beyond recognition. That's why, as Chinese leaders prepare to mark the 30th anniversary of Deng Xiaoping's capitalist reforms next month, they're also frantically pumping more than half a trillion dollars into their economy in hopes of staving off a downturn.

They have reason to worry. Economists say China's GDP has to grow between 7.5 and 8 percent a year just to keep up with the need for new jobs. Labor unrest has already broken out across the country: half of China's toymakers have gone bankrupt this year, throwing millions of factory workers into the streets, while cabbies angered by gas prices rioted and burned police vehicles in Chongqing a few weeks ago.

Tang shared their sense of frustration. Many who knew him are reluctant to talk about him publicly, fearing trouble with the authorities, and most requested anonymity before agreeing to be interviewed. But his story reveals tensions that seethe just below the surface in China.