“Because we are short of food,” said Zhuge Liang. “Our success lay in swift victory, but the enemy will not fight, and thus they weaken us day by day. Though we have worsted them now, they will soon be reinforced, and their light horse can cut off our provisions. Then we could not retreat at all. For a time they will not dare look at us, and we must take the occasion to do what they do not expect, and retreat. But I am solicitous about Wei Yan, who is on the Chencang road to keep off Wang Shuang. I fear he cannot get away. I have sent him certain orders to slay Wang Shuang, and then the force of Wei will not dare to pursue.”
So the retreat began, but to deceive the enemy the watchmen were left in the empty camp to beat the watches through the night. Cao Zhen was depressed at his recent misfortune. Then they told him Zhang He had come. Zhang He came up to the gate, dismounted, and entered.
When he saw Cao Zhen, he said, “I have received a royal command to come and to be into your arrangements.”
“Did you take leave of friend Sima Yi?” asked Cao Zhen.
Zhang He said, “His instructions to me were to stay away if you were victor, to come if you were not. It seems that our side has missed success. Have you since found out what the troops of Shu are doing?”
“Not yet.”
So Cao Zhen sent out some scouts, and they found empty camps. There were flags flying, but the army had been gone two days. Cao Zhen was disgusted.
When Wei Yan received his secret orders, he broke up camp that night and hastened toward Hanzhong. Wang Shuang's scouts heard this and told their chief, who hurried in pursuit. After about seven miles, he came in sight of Wei Yan's ensigns. As soon as he got within hailing distance, he shouted, “Do not flee, Wei Yan!”
But no one looked back, so he again pressed forward.
Then he heard one of his guards behind him shouting, “There is a blaze in the camp outside the wall; I think it is some wile of the enemy.”
Wang Shuang pulled up and, turning, saw the fire. He therefore tried to draw off his troops. Just as he passed a hill, a horseman suddenly came out of a wood.
“Here is Wei Yan!” shouted the horseman.
Wang Shuang was too startled to defend himself and fell at the first stroke of Wei Yan's blade. Wang Shuang's troops thought this was only the beginning of an ambush and serious attack, so they scattered; but really Wei Yan only had thirty men with him, and they moved off leisurely toward Hanzhong.
The secret orders sent to Wei Yan was that he was to keep back thirty men and hide beside Wang Shuang's camp till that warrior left. Then the camp was to be set on fire. After that the thirty were to wait till Wang Shuang's return to fall upon him. The plan being successfully carried out, Wei Yan followed the retreating army into Hanzhong and handed over his command.
The Shu army having retreated safely to Hanzhong, feastings were held in celebration of the event.
Zhang He, who, failing to come up with the retiring enemy, presently returned to camp. Hao Zhao sent a letter to say that Wang Shuang had met his end. This loss caused Cao Zhen deep grief, so that he became ill and had to return to Luoyang. He left Zhang He, Sun Li, and Guo Huai to guard the approaches to Changan.
At a court held by Sun Quan, the Prince of Wu, a certain spy reported the doings in the west and the damages Wei had suffered in Zhuge Liang's expeditions. Thereupon certain ministers urged on Sun Quan that he should attack Wei and try to gain the Middle Land.
However, Sun Quan could not make up his mind, and Zhang Zhao endeavored to prove to him that his hour was come by this memorial:
