The states of Qin and Zhao are close allies during the Period of the Warring States. The state of Qi launches an attack against Zhao,taking advantage of the recent death of the king and his young successor. King Zhuang of Qin has his beloved concubine Luoxia negotiate with Princess Regent Cuibi from Zhao over borrowing troops; Qin proposes harsh conditions. Unwilling to send her younger brother to Qin as a hostage, Cuibi falls out with Luoxia. The princess decides to find a champion to save her country. A senior minister recommends his foster son Qingyun and his own son. Despite his civil and military talents,Qingyun disdains officialdom. The princess pays a personal visit to Qingyun and makes him her general.Qingyun advises the princess to borrow troops from Qin lest the country be annexed by Qi.
King Zhuang of Qin arrives in Zhao and is astonished by the beauty of the princess, who has secretly become engaged to Qingyun. After Qin and Zhao join forces to repel the Qi army, the king of Qin threatens to take the crown prince of Zhao hostage unless Cuibi agrees to marry him. Qingyun is greatly depressed and loses heart, but he finally pulls himself together and rescues Cuibi. During a fierce battle with the KingZhuang, Qingyun is about to be defeated when he is encouraged by a love song played by Cuibi and turns the tables on his opponent. Eventually the king of Qin promises to make peace with Zhao. Qingyun andCuibi are married.