The film is set in the early Northern Song dynasty, AD 986, of northeastern China. Former Northern Han general and the patriarch of the Yang clan Yang Ye pledges allegiance to the new Han Chinese-ruled Song regime after Northern Han’s fall. Years later Yang’s seventh son, Yang Yansi, participated in a martial arts tournament with his father’s rival Pan Renmei’s son Pan Bao in his sixth brother Yang Yanzhao’s place to win Later Zhou’s former princess Chai Meirong’s (who is Yang Yanzhao’s childhood sweetheart) hand in marriage, which ended in the latter’s death. The following morning Yang and Pan meet with the emperor about the issue; Yang executes 30 whiplashes to his young sons as punishment. Later, Song’s border stations are burned, signaling an invasion from the Khitan-ruled Liao regime.
The Khitan army hopes to take its revenge on the Yang Clan and their followers for a past defeat that killed a Khitan general ten years previously. It was noted that the leader of the invading Khitan army is Yelü Yuan, son of the deceased Khitan general. Due to politics and Pan Bao’s death, Pan Renmei is awarded with 50,000 troops to repel the Khitan army. As punishment, Gen. Yang is given a lesser task—to lead the charge and be the scout. When the two armies meet, Pan Renmei’s lack of experience and inept leadership causes chaos among the Song army, and the Khitan forces emerge with a decisive victory. All the while Gen. Yang is trapped behind enemy lines in an abandoned town in front of Wolf Mountain. The Khitan army surrounds the town, allowing no one to leave. Pan, however, refuses to send troops to rescue Yang as revenge. This leaves Yang Ye’s wife, She Saihua, devastated as she sends her seven sons to rescue him. It is later revealed that this is exactly what Yelü Yuan wanted, and the sons fall into his deadly trap.