Lu Zhaoning's engagement to the heir of the Yongan Marquis was stolen by her adopted sister Su Wantang. Her family forced her to yield, and an imperial edict for peace marriage sent her to the northern border. Thinking it was a sacrifice, she instead encountered the new king Helian Jin, discovering that she had saved him many years ago. Facing her ex-lover's remorse and her adopted sister's malicious harm, Lu Zhaoning let go of past grudges, relied on the trade routes left by her mother, promoted cross-border trade between the two nations, broke free from secular shackles, and lived to become the universally admired Queen of the Northern Border.