The Immortal PromiseEpisode 4

Buod: Zhang Xiao Mei, commander of the Beiyi division and younger brother of the Noble Consort who's currently pregnant, has sworn revenge against the crown prince Li Ye ever since the latter set up his father and killed him. When he arrests Zhu Qing Zhu, Li Ye's best spy, he sees an opportunity to finally expose Li Ye's crimes. But Li Ye makes Qing Zhu his scapegoat to escape punishment. When Qing Zhu is sacrificed, and about to get killed by the man to whom she devoted her life and who told her they were family, Zhang Xiao Mei can't help but pity her and saves her from death before welcoming her into his mansion. As they spend more and more time together, Zhang Xiao Mei realizes that their fates have actually been intertwined for a long time, and they both fall in love. But the crown prince reappears, unwilling to let go of his ambition and even less of Qing Zhu, especially to let her be happy with another