Wentian (played by Zhao Wenzhuo) and Wanxin (played by Mo Shaocong) were brothers who loved each other very much, but they were separated because of an accident. Wentian was lucky to meet his father's guards and was rescued by them, but Wanxin was not so lucky. His old enemy, Eunuch Chu, took him away. Since then, Wanxin has become the adopted son of Eunuch Chu and a slave of the East Factory. In a blink of an eye, decades have passed. Wentian and Wanxin have grown into independent heroes. When they were young, they swallowed the extremely yin water dragon ball and the extremely yang fire dragon ball respectively. Therefore, when the two met again, the power of the two beads played a role, making them attracted to each other and became sworn brothers without knowing it. Wanxin was going to marry Bai Yutong (played by Kristy Yang), a rich girl, but Bai Yutong was weak in appearance and strong in heart. She was dissatisfied with the domineering style of the East Factory, and transformed into a female knight Jin Yanzi who robbed the rich and helped the poor, wandering around the world, and fell in love with the chivalrous Wentian at first sight.