In the height of summer in the seventeenth year of the Tianqi era, thunder and torrential rain engulf the Right Chancellor's residence. The noble young master Duan Ling goes from a pampered son to the orphan of a condemned official overnight. It is a deadly trap laid by Second Prince Xiao Heng and the powerful official Liu Song, who plot to seize the Great Yong dynasty. Xiao Heng also harbors an obsessive desire to possess Duan Ling, locking him inside the splendid cage of the prince's residence.
Su Tao, a maid secretly living in the residence, is the eldest daughter of the Xuancheng Sect. After three years in hiding, she uncovers the shocking secret that the two men are conspiring with the Northern Desert and selling out the border defenses. When her identity is exposed, she sacrifices her life to pass Duan Ling a piece of silk recording the evidence, helping him escape. With her dying breath, she entrusts her young brother, Su Mu, to him.
Bearing a deep blood feud and a promise to the dead, Duan Ling flees to Jiangnan and lies low with Su Mu for five years. Su Mu is a peerless martial artist, his sharp edge impossible to hide. After weathering life-and-death ordeals together, the two fall for each other. But peace in Jiangnan cannot last. To clear their names, they resolve to return to the capital, one wielding strategy and the other force, their blades rising together.
They use the reopening of the old case to enter the political arena, joining forces with upright officials and old allies from the martial world. Xiao Heng summons Duan Ling to the imperial study in the dead of night, tempting him with wealth and power in an attempt to imprison him once more. Su Mu provides support from outside the palace, and the evidence is revealed to the public, shaking the court and unleashing a storm across the imperial city.
In the end, the traitors are punished and the injustice is avenged. When the court summons them with high office and generous rewards, the two refuse to remain trapped in a palace steeped in blood and tears. Having weathered the palace's deadly schemes and escaped the cages of fate, they leave behind the struggles of court politics. From then on, with the mountains vast and the waters long, the two stand shoulder to shoulder, roaming the rivers and mountains for thousands of miles.
Theme: Everyone has a cage in their heart. Only by supporting one another and staying true to themselves can they endure every trial, escape obsession, and embrace their own freedom and their own world.
