Real-life figure Miyamoto Musashi was the most celebrated samurai of all time. The quintessential warrior philosopher, Musashi authored A Book of Five Rings, a theoretical guide to military strategy still used today. But the path to enlightenment is an endless journey, and to get there through violent means - by way of the sword - makes mere survival an even greater challenge.

Musashi suffers a humiliating defeat against Inshun, the second-generation master of Hozoin Temple. To prepare for a rematch, Musashi undertakes an intense spiritual and physical training regimen with a most unlikely teacher - Inshun's predecessor, the founder of the Hozoin Spear Technique. To attain the focus necessary to take on the most technically proficient and deadliest fighter he has ever faced, Musashi will first have to confront his own deep-seated personal demons.