When Emperor Taizong of the Tang Dynasty was trapped in Muyang City, Cheng Yaojin broke out and returned to the capital to recruit reinforcements. As a result, the young Luo Tong won the command and went to Muyang City with his younger brother Luo Ren to rescue him. Princess Tulu of Fan Bang fell in love with Luo Tong at first sight and decided to abandon Fan and join the Tang Dynasty. She helped Luo Tong avenge his father and killed Su Dingfang, a traitor to Tong Fan. After the Tang camp defeated the enemy, Cheng Yaojin arranged for Luo Tong to marry Princess Tulu. Zuo Yunshan used a vicious trick to kill Luo Ren and put the blame on Princess Tulu, causing the couple to turn against each other. As a result, Princess Tulu committed suicide on the wedding night.
