Just before the fall of the mighty Korean Kingdom of Goguryeo, a lone man roamed the lands causing destruction beyond imagine using Sa Shin Mu, a form of martial arts never before seen in this world. When peace suddenly returns to the land, it’s rumored that this warrior was killed by none other than his own younger brother, the first and only warrior to have truly mastered Sa Shin Mu. But just like the way Sa Shin Mu suddenly appeared, this ultimate warrior and all knowledge of his martial art suddenly disappears...
Now, 20 years after the fall of the Kingdom of Goguryeo, a new rumor is spreading that a secret manual detailing this legendary martial art has resurfaced. Will Sa Shin Mu once again dictate the fate of this new era?