"So he told the purbas."

"He became a purba. Not because of the sheep. Because they put his brother in prison on flour charges. Some July sixth, years ago."

Shan grimaced. For centuries throwing roasted barley flour into the air had been a traditional Tibetan expression of rejoicing. But July 6, the Dalai Lama's birthday, had been outlawed as a holiday, and those caught celebrating it with flour, even sometimes those caught carrying bags of flour on the day, were subject to criminal charges.

"But all these people," Shan said. "Not just purbas use it."

Jowa opened another heavy door and gestured Shan through it. "I was one of those who opened it years ago. It is one of the few safe places we have in the region. It became something of a sanctuary, for people in transit. They come usually at night, with a purba guide. Few know exactly where they are. Most stay only a few days and move on."

"Transit?" Shan asked as they started down the corridor.

"Sometimes people have to leave quickly," Jowa explained, "cross the mountains before they are arrested. Sometimes they can't take their families. But their families are known to Public Security, so their families must be protected." Public Security would use the families, Jowa meant, would take them as hostages for the return of the fugitive or just punish them in retribution.

"So, all these people- they are waiting to cross the border?"

"Some are. Some just come to help. Some come to rest or recover from injuries that can't be taken to a Chinese hospital. Others come for the quiet, to make plans."

As they walked past another group of reclining figures, a woman sat up and called to Jowa. "Thank you, thank you again," she said in a soft, shy voice, then looked at Shan with a tentative expression, as if she recognized him. As she raised her bandaged wrist, Shan realized who she was and halted.

"They were still very frightened when our people found them," Jowa explained. "Just sitting at the boy's grave, waving that charm. I said, at least give her time here, in safety, to heal her wrist. We sent people to watch their sheep."

It was the dropka woman, the foster mother of the dead boy Alta.

Shan stepped across a collection of sleeping forms to squat by the woman's side. "I hope your hand is better," he offered.

"Soon I will be able to use it, the healer here says," the woman said, bracing her broken wrist on her knee. She placed her uninjured hand flat onto something beside her as she spoke, as if she needed support. Shan glanced down. She was leaning on the charm, the sacred writing left by Gendun the day Alta had died.

"I wanted to ask you something important," Shan said. "I am sorry if the memory is still painful. But we are still trying to understand. The day when you found the killer, was the killer speaking to the boy? Asking him questions?"

The woman's brow knitted as she struggled to remember. She shook her head gradually. "Nothing. No words. Just noises."

"You said he was called away by lightning. Are you sure? Lightning is rare in the mountains this time of year."

"Of course. He saw the lightning and ran away with the boy's shoe."

"Did you recognize the noises he made?" Jowa asked her over Shan's shoulder. He spoke in Mandarin.

The woman looked at Jowa with a blank stare.

Shan glanced at Jowa and nodded. She didn't understand Mandarin.

"He did not speak," the woman said again. "Not in any language. Just noises, like an animal, when he saw the lightning."

"Can you remember the exact sound the killer made?" Shan asked.

The woman grimaced and hung her head. "I will always remember. I hear it in my nightmares now. One of the barking noises that demons make. Kow ni," she said, looking into the shadows now. "Kow ni ma swee. Like that."

"Cao ni ma," Jowa whispered. It was a curse in Mandarin. Fuck your mother. Fuck your mother, Sui.

They nodded their thanks to the woman and began to walk away.

"We should have taken him to the other place," the dropka woman said in a hollow tone behind them. "Alta wanted to go there. Maybe he would be safe there."

Shan turned back. "The other place?"

"Where the shadow clans sometimes meet. The lama field, the children call it, but only the ghosts of lamas live there."

Khitai had shown the place to the zheli, Shan recalled. It was why Batu had insisted on going there. "Why did Alta want to go there?"

The woman shook her head with a sad smile. "Lau had given them work to do, a collection of autumn flowers. Some other boys told him many flowers grew there, that Lau would be pleased with flowers from the lama field. He said the boy Khitai liked to go there, that he often persuaded his foster families to take him to the lama field for a day, that Khitai would meet the new boy with the strange accent and play in the rocks there." She meant Micah, Shan knew. Khitai liked to meet the American boy at the lama field. When the dropka looked up at Shan he thought she was going to burst into tears. "It was for Lau. They thought they had to complete their last assignment from Lau, so she could rest in peace." She looked away, and her head dropped almost as if she were falling asleep. Jowa pulled him away.

"The ghosts of lamas," Jowa repeated in a haunted voice. Shan took a moment to understand. The lama field had another dead lama now. The Yakde Lama.

"There was no storm that night Aha was attacked," Shan sighed. "We were only a few miles away."

"No," Jowa said slowly, as if fitting the pieces together as he spoke. "But the killer saw something like lightning, cursed Sui, and ran away. Which means it wasn't Sui who attacked Alta."

"She could have the words wrong," Shan suggested.

"I don't think so," Jowa said. And neither did Shan.

Jowa led him through another of the heavy security doors to a small room where four men sat at a wood plank table, studying maps. Planning. Shan recognized the young purba who had met them on the trail and driven away their truck. The youth looked up and nodded at Shan without rancor, a conspiratorial nod. The others looked at Jowa, not Shan, with unhappy, impatient expressions. A fifth man, at a table with thermoses, turned as they entered, a thin Uighur with a crooked nose. Fat Mao. Explaining that he had just arrived from Yoktian he filled two mugs with tea and handed them to the two new arrivals. Shan studied the room. Wires hung loose from several conduits along the ceiling. A tangle of pipes ran overhead, some painted red. There was a yellow sign warning of radiation exposure painted on the back of the door. The walls were almost covered with more maps, many bearing the legend Nei Lou across the top. Scattered across the maps were colored pins and bits of paper taped to their surface. Beside the maps on the table sat a portable computer.

"I told them about the boys," Jowa said. "About Gendun and Lokesh. They want to know where the murders took place, on the maps." As he spoke, one of the Tibetans pulled his chair back and gestured for Shan to join them. Together Jowa and Shan studied a map of the region and agreed on the location of the Red Stone camp, the road where Alta had been attacked, the canyon where Kublai was killed, and the lama field where Khitai was buried. The young purba inserted pins on penciled numbers on the spots, one for Suwan, two for Alta, three for Kublai, and four for Khitai. He ran the point of his pencil in the air over the pins as though to outline the route taken by the murderer, a pattern.