In 206 BCE, after Liu Bang captured the Qin capital Xianyang, he stationed troops at Hangu Pass to guard the approach. Soon, Xiang Yu marched his 400,000-strong army into Hongmen, and his advisor Fan Zeng warned, "Liu Bang's ambition is clear—he means to seize the empire. You must strike now."
A minor official named Cao Wushang, serving under Liu Bang, secretly sent word to Xiang Yu that Liu Bang planned to declare himself king in Guanzhong, appoint the surrendered Qin prince Ziying as his chancellor, and claim all the valuable treasures for himself. Enraged, Xiang Yu immediately ordered his troops to be feasted the next day before attacking Liu Bang's forces. Fortunately, Xiang Yu's uncle Xiang Bo, an old friend of Liu Bang's chief strategist Zhang Liang, slipped word of this plan to Zhang Liang late that night.
At the time, Liu Bang commanded only a hundred thousand troops, far too few to withstand Xiang Yu's massive army. So he courted Xiang Bo, forging a kinship bond with him, and heeded Xiang Bo's advice to go personally to Hongmen at dawn the next day, apologize to Xiang Yu face-to-face, and clear up the misunderstanding. Xiang Bo rushed back that very night and explained to Xiang Yu, "Liu Bang has no ambitions against you. Since he's coming tomorrow, why not treat him well and settle things amicably?"
The next morning, accompanied by Zhang Liang, Liu Bang led over a hundred cavalry to Hongmen, where he explained the situation to Xiang Yu. Hearing Liu Bang's sincere and straightforward account, Xiang Yu expressed his desire to clear up any suspicions and hosted a banquet in Liu Bang's honor. Xiang Yu's advisors Fan Zeng and Xiang Bo also attended the feast.
Before this, Fan Zeng had advocated eliminating Liu Bang to avoid future trouble. During the feast, he repeatedly signaled to Xiang Yu with his eyes and raised his jade pendant to urge him to make the decision to kill Liu Bang, but Xiang Yu remained silent and ignored him. So Fan Zeng rose from his seat, called over Xiang Yu's cousin Xiang Zhuang, and said:
"His Majesty is soft-hearted. Go in, present the wine, offer your birthday wishes, then request to perform a sword dance for entertainment. Seize the opportunity to kill Pei Gong (Liu Bang) on his seat. Otherwise, all of you will be captured by Liu Bang."
Xiang Zhuang entered as instructed, offered wine and birthday wishes, then said to Xiang Yu, "Your Majesty is drinking with the Duke of Pei. Since there is no entertainment in the army, allow me to perform a sword dance to liven things up."
Xiang Yu agreed, and Xiang Zhuang immediately drew his sword and began a dance before the banquet. Xiang Bo sensed something was wrong, so he drew his sword and joined the dance, using his body to shield Liu Bang at every turn, preventing Xiang Zhuang from making a move.
Zhang Liang saw the situation was bad and hurried to the camp gate, where he found Liu Bang's general Fan Kuai. Fan Kuai asked Zhang Liang as soon as he saw him:
“How is the situation now?” “Extremely critical. Xiang Zhuang is pretending to dance with his sword for entertainment, but his real intention is to kill Lord Pei.” Fan Kuai exclaimed, “Since it’s so urgent, let me go in and fight them to the death!”
Fan Kuai, sword in hand and shield raised, burst through the military gate. When guards tried to block him, he rammed them aside with his shield and charged in. Throwing back the tent curtain, he stood facing west, glaring at Xiang Yu with such fury that his hair stood on end and his eyes seemed to split open.
Xiang Yu gripped his sword hilt, his thighs pressed against his heels, then lifted them and straightened his waist, shouting, "Who is this visitor?" Zhang Liang replied beside him, "This is Fan Kuai, a general under the Duke of Pei." "A true warrior! Bring a cup and grant him wine."
One of Xiang Yu's attendants handed Fan Kuai a large goblet filled with a full dou of wine. Fan Kuai bowed in thanks, then rose and drained it in one gulp while standing.
Xiang Yu then presented Fan Kuai with a pork shoulder. Fan Kuai placed the meat on his shield, drew his sword, cut it into pieces, and devoured it heartily.
Xiang Yu asked again, "Brave warrior, can you still drink wine?"
Fan Kuai replied without changing his expression, "I would not flee even in death, so how could drinking wine be worse than execution? The King of Qin had the heart of a tiger or wolf, fearing only that he could not kill enough people and that his punishments were not cruel enough, which is why everyone under heaven turned against him. Your Majesty once made an agreement with the various generals: 'Whoever first breaks into Xianyang shall be made king.' Now Lord Pei was the first to break into Xianyang, yet he dared not take anything, sealed the palaces, and withdrew his army to Bashang, awaiting your arrival. As for sending generals to guard the passes, that was to guard against bandits and unexpected incidents. With such toil and merit, he has received no reward of nobility, yet Your Majesty, listening to petty slander, wants to kill a man of achievement. This is to follow the very path that led to the fall of Qin. I privately think for Your Majesty that this is not the right course!"
After hearing this, Xiang Yu invited Fan Kuai to sit down, and Fan Kuai took a seat next to Zhang Liang. A short while later, Liu Bang excused himself to use the restroom, signaling Fan Kuai to follow, and seized the opportunity to slip back to his own camp.
Later, people used "Xiang Zhuang's sword dance is aimed at the Duke of Pei" to describe words or actions that appear peaceful on the surface but are actually intended to harm someone.
Source: *Records of the Grand Historian*, "Biography of Xiang Yu"
Meaning of the Idiom: Later, the Chinese idiom "项庄舞剑" came to describe how words or actions that appear peaceful on the surface are actually intended to harm someone.