Having cultivated in the deep mountains since childhood, Xiao Nan descends the mountain upon his master's orders to fulfill a marriage contract, only to have the Xie family publicly tear up the engagement letter and subject him to extreme humiliation. However, he accidentally runs into the Lin sisters, saves the critically ill Lin Shuyun, and even pulls the head of the Lin family, whose life hangs by a thread, back from the gates of hell. The despised bumpkin instantly becomes an honored guest of the Lin family, gets engaged to the Lin family's second young lady Lin Ziqing, and moves into the Emerald Mountain Villa as a tenant. With his heaven-defying medical skills, he stirs up the winds and clouds in Luocheng, slaps various dignitaries in the face, subdues underground forces, and step by step unravels the mystery of his own fire poison and life experience. Amidst daily interactions, he also gradually melts the guarded heart of the proud and pampered heiress.