They were adjacent to Marco now. He was singing one of his songs, in the Turkic tongue, raising laughter among many of those in earshot.

Shan asked Jakli to explain.

She listened for a moment and blushed. "It is about camels. About camels making love and having trouble with their humps." As she spoke she breathed another sigh of relief. Shan followed her gaze toward a figure in the shadows of an alley that opened into the street ten feet from where Marco stood. Marco had seen the figure too. He cast a quick wink at Jakli, then spoke into Sophie's ear and dropped her reins.

The silver camel exploded into an ear-splitting bray and bolted straight through the line, scattering all those nearby. Marco shouted after her, then called for someone to catch her. More than twenty people broke into pursuit, including the figure in the alley, who ran headlong into Shan and Jakli, pushing them both to the ground while he shouted for the camel. Several hands grabbed Shan. Something moist touched his hand, and a hat was thrust low over his head. The instant he regained his feet Jakli pulled him into the crowd chasing Sophie. A moment later the camel quieted under the hands of an old Kazakh, who led her back to Marco. Jakli pushed Shan into the shadow of a doorway. He looked at his hand. It was stamped with a ring of five red stars. They wandered around the square, casually showing their stamp to the knobs they passed.

Another man was singled out for special attention at the table of officers.

"Ask someone," Shan said in a low voice, "if it is a another Tadjik."

It was, a nearly toothless old woman said, and the chill returned. Suddenly, despite Bao's desperate rush to find the subversives, Public Security wanted a Tadjik.

"The fools don't know," the old woman added. "The Tadjiks have gone to Yoktian. Director Ko is giving all of them new clothes, American blue jeans. A special tribute to the social contributions of Tadjiks."

As Jakli pulled him into the shadows at the edge of the street, Shan stared at the old woman in confusion. The Brigade was not only watching to see what Tadjiks the knobs might snare, it was separately trying to entice Tadjiks to town. So they could turn over the Tadjiks to the knobs, Shan wondered, or so they could prevent the knobs from finding Tadjiks? Or at least one specific Tadjik.

Jakli brought them bottled orange drinks from a vendor who sold goods from a rug in the corner of the square, and they sat against the wall of a building, watching the knobs like almost everyone else in the village. In another thirty minutes the line was done, and Marco and Sophie were led to the table. The village began to close in, as if expecting an entertainment. But Marco stared straight ahead and spoke in low respectful tones. He had his identity papers. When the officer finished, however, he stood in front of Sophie, his face eighteen inches from her nose, and began a loud harangue about how undisciplined she was, how animals doing work for the people should respect the people, that she had wasted the valuable time of the Public Security Bureau. Shan had once seen a tamzing held for a horse by a furious Red Guard who had been delayed on a river bridge because of the slow horse and its cart, and wondered absently if this was the same man, thirty years later.

When the officer finished he lingered, glaring at Sophie. Sophie cocked her head as if to study him, put her nose closer, and erupted in a sound that was half snicker, half bray, an action that sprayed the man with her saliva.

Everyone laughed but Marco and the officer. Marco began to urge Sophie away, but the officer pulled his pistol and held it toward her head. With a chill Shan saw Marco's hand creep inside his coat. The crowd was instantly sober, and scared.

When the shot came Shan's head jerked back in the reflexive agony instilled by hearing so many knob pistols so many times before- in public executions in Beijing, where those seated nearest were sprayed with blood and particles of brain tissue. And in the gulag, where three times he had seen knob guards shoot monks as they calmly and defiantly recited their mantras.

But the shot came from behind, he suddenly realized, near the bus, where another officer held his gun in the air. The knob by Sophie scowled but lowered his gun, and the man who had fired in warning approached him. He had the same lightless eyes as the first man but more grey in his hair. He stared at Marco for a long moment, then ceremoniously picked up the ink stamp on the table and stamped a ring of red stars on Sophie's nose.

The knobs climbed into their trucks and in five minutes were gone, escorting the bus down the Kashgar highway. Moments later the Brigade truck eased out of the square, following the knobs.

Marco was at the village water trough when they reached him, where Sophie drank long as he washed away the red ink. "Four hours. Four damned hours wasted here," he groused.

With longing in his heart Shan watched Marco steer Sophie away into the Taklamakan at a brisk trot. Then he turned to Jakli with a new urgency. "That Tadjik Hoof holds the key. We have to find him before Ko or the knobs do."

Their sturdy horses climbed for hours, following a teenage girl from the camp where they left the truck. They rode hard, trotting constantly, their horses struggling, the girl's eyes always on the trail, where patches of ice could suddenly appear to trip the horses, or on the sky, where helicopters could materialize with even worse effect. Twice they stopped at small herding camps, where each time fresh mounts were given to Shan and Jakli. None of the herders argued. At the first camp the girl said it was for the zheli boys who were dying, and the horses were quickly offered with a cup of tea. At the second a man was talking about the holy men, and when Jakli said Shan was with them, the remounts were offered without their having asked.

They arrived at a solitary yurt so high that its water ran from a small ice field a few hundred feet above the camp. A middle aged woman wearing a soiled red apron sat by a fire at the front of the yurt, threading kernels of sun-hardened cheese onto a string. A boy of no more than six stood close against the felt of the yurt, out of the wind, methodically working a butter churn. The woman nodded greetings, then broke a corner from a brick of black tea and dropped it into a kettle at the edge of the fire. Her face was friendly but sad, and Shan remembered. This was the camp of Osman's uncle, where a son had died recently of fever.

The woman poured the tea and said the herders would return by sundown, then pointed to the cushions and blankets piled high at the rear of the yurt. Shan felt desperately tired and knew his face showed it.

He was awakened from his slumber by a chorus of bleating sheep. A deep blush of pink over the western peaks was all that remained of daylight. The fire was blazing, and a grey-haired man squatted before it with a tin mug of tea. Sheep were everywhere. The yurt seemed to be an island in a sea of sheep. Shan saw two more figures in heavy dark chubas, moving among the sheep. One, an older woman, was walking toward the fire. The other, wearing a black felt cap, hung back, sitting on a rock, with a big mastiff guard dog.

There were more dogs, Shan saw. Two mastiffs lay near the fire, one with its head over the other's back, both watching Shan suspiciously as he stepped toward the fire. A smaller white dog, crawling under the sheep, emerged from the flock and ran into the yurt. When Jakli and their guide awoke they all ate bowls of yogurt with nan bread and some kind of dried meat, their hosts nodding politely but speaking more to their dogs than to their guests. Jakli provided a package of hard round candies from her bag, which were enthusiastically accepted and passed around. Finally, his hunger apparently outstripping his fear, the man in the black hat approached.