"But if you were able to make him do your bidding, you must urge him not to do bad things, and to do some good for the people. Promise me!"

"What a funny thing to say. Do you really think I would be unwilling to do anything you asked me to do?"

"Thank you," Chen said, and she smiled.

They walked along a stretch of the wall hand-in-hand.

"I just thought of something," said Princess Fragrance.

"What?"

"I am very happy today, but is it because of this beautiful scenery? No. I know it's because I am with you. As long as you are by my side, I would think even the most ugly place on earth was beautiful."

The happier she was, the more uncomfortable Chen felt. "Is there anything you would like me to do?" he asked.

"Oh, but you have already done everything. You have always given me everything I wanted, even without asking for it." She pulled the snow lotus from her pocket. The flower was now dry and withered, but it still possessed a strong fragrance.

"There is only one thing you refused to do," she added with a smile. "And that is to sing me a song."

Chen laughed. "It's true," he said. "I have never sung you a song."

Princess Fragrance pulled a face. "Well, I'm not going to sing for you any more either."

"I remember my mother's maid servant singing several rhymes when I was young. I'll sing one for you now, but you're not allowed to laugh."

She clapped her hands in delight. "All right! All right! Sing!"

He thought for a moment, and then began:

"The light rain falls

The wind blows in squalls

Someone outside saucily calls,

I think it's my loved one,

And softly curse him round and right.

But looking once again

I see it's not, and jump in fright."

After he had finished, Chen explained the words of the song in the Muslim tongue, and Princess Fragrance laughed.

"The lady's eyesight was not too good, apparently," she said.

They explored the top of the wall, which consisted of battlements on the northern side, a stone hand rail on the other and a walkway in between. Every three hundred feet or so, there was a watchtower. They came to a beacon tower, and Chen thought of the time Huo Qingtong had burned wolf dung as part of her plan to destroy the Manchu army. He wondered again if she was alive or dead, and his sadness increased.

"I know what you are thinking," said Princess Fragrance.

"Do you?"

"Yes. You are thinking of my sister."

"How did you know?"

"When the three of us were in the Secret City together, I could see how happy you were in spite of the danger. Oh, you mustn't worry so!"

He took her hand, "What do you mean?" he asked.

She sighed. "In the old days, I was just a child. I didn't understand anything. But every day I was in the Imperial Palace, I thought about the times we were together and realised many things that had not occured to me before. My sister loved you all along, and you love her, don't you?"

"Yes. I shouldn't try to deceive you."

"But I know you truly love me too. And without you, I cannot live. So let's go and find my sister quickly and we can all live happily together forever. Don't you think that would be lovely?"

Her eyes and face radiated happiness. Chen squeezed her hand. "You have thought it out perfectly," he said softly. "You and your sister are the nicest, the best people in the world."

Princess Fragrance stood looking out into the distance, and noticed the sun glinting off a body of water to the west. "Let's go and have a look over there," she said.

They made their way across the hills, and came upon a clear spring bubbling merrily out of a crack in the rocks.

"I will wash my feet here, is that all right?" Princess Fragrance asked.

"Of course," Chen replied with a smile. She took off her shoes and socks and stepped into the water, relishing the coolness as the crystal clear water flowed around her milk-white feet. Chen happened to see his own shadow on the water, and realised the sun was already sinking into the west. He reached into his bag and pulled out some food for them. Princess Fragrance leant against him and wiped her feet dry as she ate.

Chen gritted his teeth. "There is something I must say to you," he said. She turned and put both her arms round him, resting her head on his chest.

"I know you love me," she said quietly. "I understand. You don't have to say it."

He cringed and swallowed what he had been about to say. After a while, he started again: "Do you still remember Mami's last testament that we read inside the White Jade Peak?"

"She is living in Heaven now with her Ali. That's the way it should be."

"You Muslims believe that after good people die, they will live forever in paradise, is that right?"

"Of course that's what happens."

"When I return to Beijing, I will go and find an Islamic Imam and get him to teach me so that I can become a good follower of the Muslim faith," said Chen.

Princess Fragrance was overjoyed. She had never guessed he would be willing to voluntarily join the Muslim faith. "Oh my brother," she said looking up at him. "Will you really?"

"Definitely."

"You're willing to do even that because of your love for me. I never dared to hope for such a thing."

"Because in this life," Chen continued slowly, "we will not be able to be together. So I want to be sure that after death, I can be with you every day."

The words struck Princess Fragrance like a clap of thunder. After a moment's silence, she said in shaking voice: "You…what are you talking about? We can't be together?"

"No. After today, we will not be able to see each other again."

"Why?" Her body quivered and two large tears fell onto his gown.

Chen embraced her tenderly. "If it were possible for me to be with you, I would be content even without food or clothing, even if I was beaten and humiliated everyday. But do you remember Mami? The good Mami was willing to leave her true love Ali in order that her tribe would no longer be oppressed and bullied by Sanglaba and was even willing to go and allow herself to be violated by him…"

Princess Fragrance's body went limp. "You want me to give in to the Emperor?" she whispered. "You want me to kill him?"

"No, he is my blood brother." He told her everything about his relationship with Qian Long, and the Red Flower Society's plans, about the oath sworn in the Six Harmonies Pagoda, and of Qian Long's demand earlier that day. As he spoke, Princess Fragrance realised that what she had been longing for day and night and thought she had achieved, was slipping from her grasp again. She was overwhelmed by a wave of panic and fainted away.

As she came to, she felt Chen holding her tightly, and was aware of a damp patch on her dress soaked by his tears. She stood up.

"Wait for me here," she said softly, and walked towards a large flat rock in the distance where she prostrated herself in prayer towards the west. She appealed to the True God, Allah for guidance on what she should do. The pale sunlight glanced off her white dress, her back presenting a picture of both great melancholy and warmth. After a while, she walked slowly back.

"Whatever you want me to do, I will do," she announced.

Chen jumped up and ran over to her, and the two embraced each other tightly.

"If I had known we had only today, I would have wanted you to hold me the whole day rather than come here," she whispered. Chen kissed her, unable to answer.

A long time passed. Then suddenly, Princess Fragrance said: "I have not had a bath since I left home. I am going to have one now." She began to take off her outer gown.

Chen stood up. "I'll go over there to wait for you," he said.

"No! No! I want you to watch me. When you saw me for the first time, I was bathing. Today is the last time…After you have seen me, I want you to never forget me."