The Chinese government does not like being embarrassed. In April 2003 Dr. Jiang Yanyong became a Chinese folk hero after disclosing the true extent of Beijing's SARS epidemic and exposing a government cover-up. The retired Army surgeon, who is one of China's best-known antigovernment critics, surely saved lives with his alert; indeed, his name was even bandied about this month as a contender for the Nobel Peace Prize. But Jiang, 73, wasn't exactly rewarded for his effort. After a seven-week detention this summer, the whistle-blower remains under a loose form of house arrest--unable to leave his residential compound without permission. Three weeks ago Jiang was permitted to leave home and enjoy a meal in public with relatives and friends. It was his second outing in a matter of days. Ever since Hu Jintao assumed leadership of the military as well as the government during the Communist Party plenum in mid-September, Jiang (who remains an active member of the People's Liberation Army) has allowed himself to hope that he might be freed soon.

That hasn't happened, even though Jiang hasn't been charged with any crime. Instead the retired head of surgery at Beijing's Military Hospital Number 301 is living in an ambiguous, extralegal state known as shanggui, deprived of full freedom pending results of an intraparty investigation. Family members were told he'd be freed on Sept. 15. As the magic day neared, Jiang dusted off his bicycle, filled the tires and looked forward to riding around on the streets of Beijing once again. But there's been no news since, and Jiang has taken to showing his impatience by riding his bike in circles inside his residential courtyard.

Last year when Jiang revealed that the number of SARS patients in military hospitals was much higher than reported, state media praised him as an "honest doctor," even as a "SARS hero." But this February Jiang blew the whistle again--this time on a much more sensitive episode in Chinese history. In a letter addressed to the top leadership, Jiang asked the government to reassess the June 1989 pro-democracy demonstrations at Tiananmen Square and acknowledge that the protesters were "patriots." Jiang recounted his anguish at treating youthful victims of the crackdown, in which "tanks, machine guns and other weapons [were used] to suppress the totally unarmed students and citizens, killing hundreds of innocent students... Then, the authorities mobilized all types of propaganda machinery to fabricate lies," he wrote in his letter.

On June 1, as the 15th anniversary of the crackdown approached, Jiang and his wife were detained on their way to the U.S. Embassy to pick up a visa to visit their daughter's family in California. In detention, Jiang submitted to regular "study sessions"; he was forced to watch, over and over, video footage of the Tiananmen bloodshed that authorities had compiled to support their view of the protests as a "counterrevolutionary riot." "You see, this is what the people you're supporting are really like," his captors told him, according to one source.

After 49 days Jiang was allowed to go home on the condition that he not speak to the media. He remains largely confined to the courtyard of a residential complex for retired military doctors; its gates are guarded by police who require Jiang's visitors to register their names. Jiang and his family were delighted in August when he won a Ramon Magsaysay award--Asia's version of the Nobel Peace Prize--for forcing the truth about SARS into the open, but Chinese authorities pressured him to write a letter saying he didn't deserve the prize. When a group of former classmates visited him on Sept. 14 to mark the day they joined the military together 50 years earlier, Jiang wasn't allowed to leave home for a reunion meal.

Jiang's friends worry that his shadowy, limbo existence could drag on indefinitely. They point to the case of Jiang's former schoolmate Bao Tong, who was a top aide to the then Party Secretary Zhao Ziyang in June 1989. After showing some sympathy with the Tiananmen protesters, Zhao was purged and Bao was jailed. Bao was released in 1997, but he's still followed by security agents every time he goes out. When Bao manages to shake his tail, he sometimes visits Jiang for a rare, brief reunion.

According to a source close to the case, Jiang "has some confidence in [China's] new leaders." The old leadership resented Jiang for lifting the lid on the SARS cover-up because it made the government of former president Jiang Zemin look bad. But even if the doctor regains his freedom, he doesn't plan to abandon his habit of telling the truth. Over the summer he told relatives that he hopes to use his high profile to help tackle other urgent medical problems--such as the country's mushrooming number of victims suffering from HIV or AIDS.