In the late 16th century, Admiral Yi Sun-sin of the Joseon Dynasty faces overwhelming odds as he prepares to defend his nation against a massive invading Japanese fleet. Recently stripped of his rank and reinstated only out of desperation, Yi must contend with a demoralized and vastly outnumbered force of just thirteen ships. With unyielding determination, he leverages his expert knowledge of the local waters, particularly the perilous currents of the Myeongnyang Strait, to level the playing field against the invasion force.

Through masterful strategic planning and inspiring leadership, Yi Sun-sin and his crew face formidable challenges and internal strife. The odds favor the enemy whose superior numbers seem insurmountable. Yet, with unwavering resolve, ingenious tactics, and an unbreakable spirit, Yi seeks to turn the tide of war and protect his homeland from conquest. The narrative showcases his tactical brilliance and the intense naval battles that test the limits of human endurance and courage.