Go Su-hyeon travels to the capital to avenge her mother under the guise of honoring her engagement to the commander-in-chief's second son. There, she unexpectedly crosses paths with Han Ju-won, her fiancé's elder brother, who shamelessly pursues her despite knowing her identity. Every step Su-hyeon takes toward vengeance draws her deeper into Ju-won's grasp. He has only one warning for her. "Don't run. You're mine."