"Someone at the museum may have lied to him," Tan suggested.

"No. Madame Ko checked this morning. No one ever called the museum about the costumes."

"But Jao would never have ordered the costume sent back from Lhasa to Lhadrung. There would be no reason," Tan said tentatively.

"Did you ever hear that his chop was stolen? It would be very disturbing for a prosecutor to lose his seal. Something the military governor should have known about."

"It was only his personal seal."

"I think his personal seal was accessible to someone here in Lhadrung, and they used it to stamp the card that was later put on the museum box."

"You're saying Miss Lihua is lying?"

"We need her back here, right away."

"You saw her note. She's coming." As Tan dropped the fax on the desk, they became aware of Madame Ko standing excitedly at the door, uninvited but apparently unwilling to leave. She raised her hand and made a quick, victorious fist in midair. Tan sighed and gestured for her to enter.

"So Jao was to meet this man Deng in Beijing. For what?" Tan asked.

"To review water permits in Lhadrung," Madame Ko reported. "Jao wanted to know who held the rights before the Americans."

"And Comrade Deng of the Ministry of Agriculture. He had the answer?"

"All the records were still in the original boxes from Lhasa. That's why he was so unhappy that Jao never arrived. Said he had spent hours sorting through them."

"For some stranger from Tibet, he did all that?"

Madame Ko nodded. "Comrade Jao said that if they found what he expected that he would want Deng to go with him straight to the Ministry of Justice headquarters. A big case, he said. Deng would be commended to the Minister himself."

Tan moved to the edge of his seat. "It would have been one of the agricultural collectives," Tan asserted.

"Exactly," Madame Ko confirmed.

"You asked him?"

"Of course. It's part of our investigation," she said with a small conspiratorial nod to Shan.

Tan cast an impatient glance at Shan. "And?"

"Long Wall Farm."

Tan asked for tea. "She acts like she just solved our mystery," he sighed as Madame Ko left the room in an excited bustle.

"Maybe she did," Shan said.

"This Long Wall collective is significant somehow?"

"You recall Jin San, one of the murder victims?"

"Jao prosecuted one of the Lhadrung Five for his murder."

"And in the process discovered that Jin San operated a drug ring."

"Which we eliminated."

"Perhaps you forget that Jin San was the manager of the Long Wall collective."

The colonel lit a cigarette, studying the ember as it burned. "I want Miss Lihua back here," he suddenly barked toward the open door. "Get her a military plane if you have to."

He drew deeply on his cigarette and turned to Shan. "That opium operation is finished, fell apart after Jin San died. Drug sales in Lhadrung have stopped. Drug cases have disappeared at the clinic. I was officially commended."

Shan laid out the photo maps depicting the unexplained license area, the same maps Jao had seen. "Can you read these photos?"

Tan went to his desk and retrieved a large magnifying glass. "I told you. I commanded a missile base," he grunted.

"Yeshe studied the maps yesterday. The new road. The mine. The extra license area to the northwest. He was confused about something. This is the license area for four consecutive months." Shan pointed to the first map. "Winter. Snow. Rocks and dirt. Indistinguishable from the rest of the terrain."

He chose not to speak of Yeshe's other discovery. The computer disks taken by Fowler had indeed been inventories. Half the Chinese-language files had even matched the English files. But the other files had been inventories of munitions, of soldiers, even of missiles located in Tibet. Yeshe's hands had trembled when he gave them to Shan. Together they had taken them to the utility building at Jade Spring Camp and burned them in the furnace. Not for a moment had Shan considered the data on the disks to be genuine. But Yeshe and Shan both knew it made little difference. Public Security was unlikely to be concerned about such a fine point if it found the disks with a civilian. As he had watched the furnace flames, Yeshe had asked for leave to go to the 404th. Civilians were gathering, he had said.

"Not entirely," Tan observed, and used the lens. "There's terracing. Probably very old. But you can see traces of it. Faint shadow lines."

"Exactly. Now, a month later." Shan flipped to the next map. "The slopes are green now, faintly green. But far more so than the rest of the mountains."

"Water. Just means the terraces still catch the water," Tan said.

"But a month later. Look. The color is inconsistent. A blush of pink and red."

Tan silently leaned over the map. He studied it with the lens from several angles. "In the developing process. Sometimes there are anomolies. The chemicals create false colors. Even the lens. It doesn't always react to visible light accurately."

"I think the colors are exact." Shan set down the last map. "Six weeks ago."

"And the colors are gone," Tan observed. "No different from the adjoining slopes. Like I said, a developing fault."

"But the terraces are gone, too."

Tan looked up in confusion, then leaned over the map with his lens.

"Somebody," Shan concluded, "is still growing Jin San's poppies."

Shan hated helicopters. Airplanes had always struck him as contrary to the natural order; helicopters seemed simply impossible. The young army pilot who met them at Jade Spring Camp did little to relieve his anxiety. He flew a constant two hundred feet off the ground, creating a roller-coaster effect as they moved over the undulating hills of the upper valley. On Tan's command he banked sharply and began a steep ascent. Ten minutes later they had cleared the ridge and landed in a small clearing.

The terraces were ancient but obvious, built up with rock walls and connected by a worn cart path. Their spring crop had already been harvested. The only sign of life was thin beds of weeds, rising out of the terraces through a carpet of dead poppy leaves.

"The rocks." Tan pointed to a flat rock, then another, and another, all at regular intervals in the fields, ten feet apart. Shan kicked over the nearest. It covered a hole, three inches wide and over twenty inches deep. Tan kicked a second rock, and a third. They all covered similar holes.

Under a high overhanging rock Tan found a stack of heavy wooden poles, eight feet long. He tried one in a hole. It fit perfectly. In the shadows under the rock Shan found the end of a rope. He pulled it without success, then called Tan. Together they heaved and a huge bundle of cloth appeared, wrapped in the rope. No, Shan quickly realized as it emerged into the light, it wasn't cloth. It was a huge military camouflage net.

The silence was broken by a shout from above.

"Colonel!" the pilot called as he ran down the slope. "There was a radio message. They are firing machine guns at the 404th!"

Tan ordered the pilot to circle over the prison. There were three emergency vehicles, lights flashing, sitting at the front gate. Four groups of people could be discerned, each clustered together, like pieces of a puzzle waiting to be connected. In the prison compound sitting in a compact square were the prisoners. Shan searched for bodies, for litters of figures being carried to the ambulances, but he found none. Outside the wire in front of the mess hall were the prison guards, in their green uniforms, standing in a crescent facing the prison compound.