Li Tianming, a beggar at rock bottom, meets Xiao Wenxue, the most noble woman in the world. A daughter of a prestigious aristocratic family, she shockingly proposes to him on the street and even elopes with him despite her family's fierce opposition. But she has no idea of the "terrifying true identity" of the man she loves—his real form is the crown prince of Great Xia, driven from his country by the second prince's coup. After wandering, he inherited the secret arts of the Underworld King and transformed into the world's most fearsome overlord, wielding ultimate martial arts and deadly poison. As the elopement scandal between the noble lady and the beggar stirs up society, the rumors reach the ears of the second prince, who plots assassination. Assassins are sent one after another. Yet Li Tianming smiles quietly. All of it is merely a move to reclaim the throne.