Twenty years after the Hae clan, a family of masters of the world's greatest martial arts, the Unsasim method, was wiped out, Mak Gwan, the head of Dongbi Academy, a school dedicated to documenting and reporting on martial arts, disappeared after receiving an invitation. Mak Mun-gun heads to the Yongmun Inn on Sachwi Mountain, as specified in the invitation, to find his master.