"I am writing this letter while wiping away tears," Nguyen Thi Hoan wrote to her parents in a letter she mailed secretly. "Please come here and save me."

HANOI -- Jobless and destitute, Nguyen Thi Hoan felt her luck was about to change. She had just arrived here one sultry June morning two years ago, and almost at once a kindly woman offered her a Job in a candy factory.

It was a trap. Within hours, Miss Hoan was spirited across the Vietnam-China border at Lang Son, 160 kilometers away, by one of the gangs that kidnap young women and sell them to be brides in China.

For several days, the 22-year-old was trucked and traded around southern China, changing hands four times before finally meeting the man who would be her husband. '1 am writing while Wiping away tears," she told her family in a letter she mailed secretly. "Please come here and save me."

Bride-buying, a Chinese tradition that the Communists largely stamped out, has seen a resurgence with the country's surging economy. Starting in the 1980s, "women were taken from poor areas, and sold to some areas that had recently gotten richer," says Ding Lu of the All-China Women's Federation, a Chinese non-governmental organization. In the 1990s, another factor contributed to the bride shortage. Chinese statistics often are unreliable, but Chinese demographers agree that more women than men have abandoned Chinese villages for big-city Jobs, leaving the countryside brimming with bachelors.

The severe shortage of women "is going to get very much worse," says Edward Tu, a demographer at Hong Kong University of Science and Technology. He says that the one-child policy, dating back to 1979, has amplified a traditional preference for sons. In Coming years, the disparity could produce a million excess bachelors a year for four decades, he estimates.

The disparity has already spawned international kidnapping rings. "What's new is cross-border traffic," Ms. Ding says. The women come from Russia, North Korea, Myanmar and Laos, human-rights groups say. But most are Vietnamese, according to the All-China women's Federation, in a trend abetted by Vietnamese poverty and a long, porous border. More than 10,000 women from Vietnam are in China illegally, according to rough estimates by the International Organization for Migration. Beijing and Hanoi recently opened formal talks on the matter.

The pretty ones are sold as brides, says Nguyen Thi Phuong Thi of the Vietnam Women's Union, a Communist Party arm that monitors the problem. "The ugly ones go to brothels."

It was June 1997, and in the commune south of Hanoi where Miss Hoan lived with her parents and four siblings, the rice harvest was poor. Hoping to boost the family income, she and her eldest brother, Nguyen Khac Hien. decided to look for work in Hanoi. They didn't have enough money for two tickets, so Miss Hoan took the hour long bus trip; he rode his bicycle.

Stepping off the bus in the capital alone and wearing peasant's clothes, Miss Hoan probably looked the very image of a gullible country girl. "A friendily woman came up to me right in the street and offered me a job," Miss Hoan says.

It sounded like a good deal -- $37 a month in a county where the monthly average is less than $25. Miss Hoan started at once, stacking bags of sugar in a Hanoi warehouse. The kindly woman praised her work, and then asked Miss Hoan to go for a drive to pick up supplies. "It all seemed so normal," Miss Hoan recalls.

By late afternoon, the car turned onto a dirt path and stopped. The woman led Miss Hoan on a 20-minute walk to a mud-brick hut, asked her to wait and left. What Miss Hoan didn't know was that she had Just walked across the Chinese border.

Night fell. Exhausted, she nodded off on the dirt floor. Suddenly, she felt someone poking her and saw a fat Chinese woman. "You'are on Chinese soil now," the woman said. "You're going to be married."

'Straying Cows'

Some details from Miss Hoan's tale are hard to confirm. But the family who eventually bought her acknowledges doing so, and researchers and aid workers say the experiences that Miss Hoan and her brother described in hours of interviews are typical.

Rising unemployment in Vietnam provides easier prey for people trafficking in Vietnamese women, who call their victims "straying cows." Dang Canh Khanh, an associate professor at the Youth Research Institute in Hanoi, a government think tank, says the promise of a job is a common trick. In fact, he and aid workers say some women cross the border willingly on promises that they will be well cared for.

Their young victims may trust the bride-brokers all the more because the traffickers often are Vietnamese women themselves. Former brides or prostitutes in China, they have the advantage of being able to move between the two cultures, says Pham Kim Ngoc, a researcher at the Center for Gender, Family and Environment Development, a research Institute in Hanoi.

It's a lucrative business, but obviously clandestine, making it hard to nail down all the details of how it works. At the border, where supplies are highest, a young woman is worth $250 to $800, with $50 to $100 of that, still a small fortune, going to the initial kidnappers, and the rest kept by brokers or traders who provide brides directly to buyers. The brides command a higherprice in more remote regions, but the longer a trader holds on to a woman, the greater the chance of running into the authorities. So it isn't uncummon for a trader to make a quick deal near the border, then return to repurchase the bride for a richer transaction inland.

At the hut where Miss Hen was being held, half a dozen more women arrived. She befriends one of them, a 15-year-old named Tran Thi Nham. "She was scared too." Miss Hoan says.

Auction Preview

The next day, while their traffickers haggled over a sale, the two Trade a daring escape. They sprinted from the bus that was transporting them and into rice paddies. They waded for hours, slept in a cow-shed, and early the next morning hitch-hiked to the border, arriving at dusk. There, the famished pair was befriended by a man offering them rice and fish.

Miss Hoan and Miss Nham sat down to eat -- and were promptly kidnapped again. They had walked straight into the home of another trafficker.

Hours later, the two women were "publicized" -- traffickers' parlance for an auction preview. Old women and their sons came to inspect the goods. While Miss Hoan didn't understand the language, she knew what was up by the gestures being made around her. She and Miss Nham were sold for around $350 apiece to a brothel. "I knew because of the pornographic pictures on the walls," Miss Hoan says. Her friend remained there, but after a day, Miss Hoan was traded for the last time and put on a bus. A two-day ride on back roads to avoid detection brought her to her final destination.

Four months later, her family received the first letter from Miss Hoan, postmarked Sept. 7, 1997. "Parents, please forgive your naughty daughter who looked for a job without your permission," Miss Hoan wrote.

Back in June, her brother had pedaled into Hanoi about three hours after his sister. Mr. Hien went to the bus station, and when he failed to find her there, he feared a the worst. Migrant workers at home had told him of young women who had disappeared this way. As he scoured the city, the word on the street wasn't reassuring.

Mr. Hien says he soon turned to planning a rescue. He knew the perils of China well. In 1990, he traveled through the south of the country to get to Hong Kong, where he hoped to find work. But he was captured by authorities as an illegal immigrant and spent seven years in a Hong Kong refugee camp for Vietnamese.

Meanwhile, letters continued to trickle in. The little money and liberty Miss Hoan got from her husband went toward these intermittent messages, each more desperate than the last. The loneliness was unbearable, she wrote in that first letter, except for the company of the many other Vietnamese bridges.

She learned that troublemakers were sold into more remote areas. Vietnamese kidnap victims have been found as far away as Tibet. So she abandoned thoughts of another escape attempt. "Hoan dares not flee." says a letter postmarked Nov. 16, 1998.

Unable to read or speak Chinese, Miss Hoan wasn't sure Where she was. But her letters offered clues. She was able to describe her home as a tea plantation near the town of Ying De - which is four hours north of the Chinese city of Guangzhou - and she was able to draw a crude map with local landmarks.

A Brother to the Rescue

Finally, Mr. Hien felt he had enough information to travel on. He speaks a little Chinese, so he would pretend to be a local. But the risks were high. He was told that men who try this "never come back." His parents begged him not to go. While he was in Hong Iong, his mother thoughthe was dead. She wasn't prepared to lose him attain. "She said she could live with losing a daughter, not a son," he recalls.

He left this past March, carrying the equivalent of $100. He bribed his way across the border for $3. Lacking the proper paperwork. he sweet-talked his way past a female bus conductor for the two-day trip to Guangzhou.

Three days later, he was standing at nightfall at the edge of the Han Kou Tea Plantation, Group Nn. 6, a row of 20 one-room houses at the end of z dirt path. The Group No. 6 village was nestled in a lush valley surrounded by jagged limestone out-crops - a landscape oddly reminiscent of northern Vietnam.

He hid in tea bushes until the first brazier fires were lit the next morning, and then strolled into the village to find his sister cooking rice for the family breakfast. He was shocked by the dark circles around her eyes. the gaunt features of a young woman who "used to be so plump and pretty," he recalls. Miss Hoan couldn't stop sobbing, But as happy as she was that her big brother had answered her pleas, she also feared for him.

His rescue strategy'. was simple but vague. He would befriend the villagers to lower their guard, and then watch for an opportunity to leave. He told the neighbors he merely wanted to visit his sister and her new husband, Ng Joy Yip, who was away at his job at a Christmas-tree factory. (Miss Hoan used terms like "husband" and "in-law" when describing her experiences, but she and Mr. Ng weren't officially married.)

Mr. Hien socialized with village elders. "I drank a lots of tea," he says. Nights he slept on his sister's floor.

His sister's in-laws were suspicious, but as days passed, Mr. Hien's rapport- building plan took root. It was helped by the fact that many of the villagers were ethnic-Chinese Vietnamese who had fled Vietnam during a brief invasion by China in 1979. That border skirmish was just the latest in what many Vietnamese consider a centuries-long series of Chinese insults that have shaped Vietnam's self-image.

Easing Their Vigilance

The bitter relations are woven into Vietnam's culture. Nearly every Vietnamese town has a street named for the Trung sisters, famous for briefly ousting some Chinese invaders 1,000 years ago. "The tale of Kieu," a nation-defining epic poem, tells of a Vietnamese heroine who is sold to foreigners and raped, but who keeps fighting back - like the fiercely independent Vietnam. The 1979 incident continued the cycle. The Chinese invasion flatten the border town of Lang Son, and the crossing didn't reopen until the 1990s.

Now it's home to a bustling trade in bikes, ceramics, shoes -- and Vietnamese women.

At the tea plantation, Miss Hoan's in-law' were finally easing their vigilance. Mr. Hien decided 1t was time to make a run. On the appointed day, before dawn, he shook his sister awake. Desplte the urgency; he recalls. "she fussed around packing things and getting dressed!" Easing open the latch of the front door, they got about 90 meters dawn the road.

Suddenly, they were surrounded by villagers armed with farm tools. Mr. Hien says they threatened to kill him. After "many, many apologies" the stand-off ended, he says. But it was clear that he and his sister wouldn't be given another chance to leave. Mr. Hien decided to rethink his rescue plan.

Real Plans

A few days later. Miss Hoan's husband, on a break from the Christmas-tree factory, appeared, and Mr. Hien announced he was ready to go back to Vietnam - without his sister. It was wrenching news for Miss Hoan, but in fact, her brother was concealing his real plans from her. He was going to the Vietnamese consulate in Guangzhou to get some help. "She's too trusting to keep a secret." he says, smiling.

At the risk of being promptly deported himself, since hc was ill the country illegally, Mr. Hien managed to persuade consulate officials to help him. With the aid of them and Chinese police, his sister was set free a week later. Brother and sister headed straight for Vietnam. They left behind them confusion and bitterness.

"We were cheated," says Ng Zi Fong, Miss Hoan's mother-in-law. MissHoan didn't work very hard, she says, but She was a hefty investment. The family had to borrow from neighbors to buy her. She cost about $700. not to mention the 5130 in fines they had to pay after her husband was arrested for breaking, the law against bride- buying.

Yet they also say that they regarded Miss Hoan as more than mere property. They say they are hurt that she would want to go. She "left without Saying good-bye." one family member says. "She was even wearing my earrings," Mrs. Ng gripes.

The family's ambivalence toward Miss Hoan - a combination of concern for her and resentment over an investment gone bad - comes out in conversation with Ng Gum Bo, an uncle of Ng Joy Yip and the bride-broker of the Han Kou Tea Plantation. He says that "It was't convenient" to let Miss Hoan go, adding, "what if something, were to happen to her?"

During a recent interview with the family, chickens scratch around the doorway of Mrs. Ng's house. Poor families like the Ngs can't persuade local women to marry their sons, says Ms. Ding of the China Women's Federation. And when they buy Women from even poorer villages, "they don't realize they are cornmitting a crime." If anything, she says, "they think the people who take their wives away are the criminals."

The Ngs are a proud clan. They left Vietnam as wartime refugees with almost no possessions. Today, thanks to paychecks sent home by Ng Joy Yip and to his uncle's profitable business, "we don't need to work the plantations anymore," Mrs. Ng says. Nevertheless, their one-room home, with its black-and-white television set, attests to he family's meager buying power. And Chinese brides are more expensive than Vietnamese ones, costing from $1,250 to $2,500, says Ng Gum Bo, the bride- broker.

Asked if the family plans to buy another bride for Ng Joy Yip, his uncle says: "It's hard to say." Financially, he adds, "we're still recovering from the last one."

Ng Gum Bo says he has lost count of how many brides he has bought and sold, but a sense of the business can be gleaned from Mr. Hien's observations during the two weeks he stayed at the plantation. He recalls seeing groups of Vietnamese women arriving every night at the uncle's house to he auctioned off. "I saw them crying all day," Mr. Hien says.

Some begged him to take them back to Vietnam. He met a 50-year-old Vietnamese woman who came to the village looking for her daughter, but the younger woman had already been traded.

At a neighbor's house just a few doors down from where Miss Hoan used to live, a new Vietnamese bride has just arrived. Her name is Thiet, says an old woman nearby, who is watching the newcomer closely while she sits on a doorstep, peeling cucumbers.

For Miss Hoan and Mr. Hien, the border brought a final gantlet. As the two approached the crossing, five groups of men approached him by turns and offered to buy his sister. Once across, the two celebrated with a meal of pork, vegetables and rice - "the most delicious food I've ever eaten." Miss Hoan says.

By this past May, they were safely back in Hanoi. "You saved me," Miss Hoan says to her brother in their tiny apartment, where they described their odyssey in a series of lengthy interviews. She is reverential in his presence. Sitting with her hands olded, she glances to him lor approaval before speaking. She fiddles with an electric fan to make sure it is cooling him.

He gently ribs his sister, and takes great pride in having rescued her. "I had to do this before I could find a wife and make a nice family of my own." he says. However, he didn't reach her quite soon enough. At the time of this interview, Miss Hoan was eight months pregnant. The shame kept her from reuniting with her parents, even though she had been back in her homeland for a month.

Damaged Goods

We can't afford to keep this baby," her brother declares. Miss Hoan listens, staring quietly into the distance.

On June 20, Miss Hoan gave birth to a daughter at the Hanoi Gynecology Hospital. When she checked out, she reluctantly left her baby behind as an orphan. She and her brother have been evicted from their Hanoi apartment because the landlord feared the birth would bring misfortune to his home.

She still hasn't gone back to her village. That must wait until she "looks better," she says. to preserve her family's reputation in the eyes of their neighbors.

As for her future, Miss Hoan worries that she's damaged goods and won't be able to marry. "No one will want to share my burden," she says.

Joanne Lee-Young in Hong Kong and Matt Forney in Beijing contributed to this article.