Martial arts masters Ken and Ryu are brought together by the mysterious death of their master but now the two warriors must overcome a challenge unlike any they've faced before. Increasingly disturbed by the dark energies building within him, Ryu is unexpectedly confronted with the appearance of Shun - a boy claiming to be the long-lost brother he never knew. Soon, signs of their common lineage are revealed as Shun enters a martial arts competition and manifests the same fearsome Dark Hadou. But before Ryu has the chance to consider whether Shun's timely appearance might be more than coincidental, agents of the insidious Shadowlaw organization kidnap the boy. To recover the child, Ryu must undertake the ultimate journey of self-discovery and learn to control the power threatening to consume him.