Dayan's third prince, Su Chen, is reduced to a hostage prince. Appearing as a good-for-nothing, he actually harbors malevolent Qi, relying on reading to suppress it and grow rapidly stronger. Daxuan's eldest princess, Xuan Yingxue, disguises herself as a maid to lurk and observe, gradually developing romantic feelings. He startles everyone at a poetry gathering, guides the princess to comprehend sword intent, and defeats a prince in the arena; later, he acknowledges his maternal clan, the Shangguan family, changes his name to Shangguan Chen, is conferred as the Marquis of Xiaoyao, and enters the academy to lecture. Dayan's assassinations continue endlessly, and the political winds of both nations surge violently. Carrying the Heavenly Evil Sword Spirit, Su Chen no longer hides, avenges his mother, and sweeps across the world.