In the aftermath of the King of Iron Fist Tournament 4, a brutal clash between father and son — Kazuya and Jin — erupts at Hon-Maru, deep in the Mishima Zaibatsu headquarters. Jin emerges victorious, and a contemptuous Heihachi then takes him on himself, only to be defeated as well. With his dark wings spread and rage threatening to consume him, Jin abruptly regains control of himself and spares Heihachi, telling him to thank his mother, Jun Kazama, before taking flight into the night.
The silence is shattered by approaching aircraft, as a swarm of Jack-4 robots crashes through the ceiling. Heihachi at first suspects Kazuya, but realizes his son is just as stunned by the attack, and the two reluctantly fight side by side against the endless waves of machines. When Heihachi begins to tire, Kazuya betrays him — hurling him into the heart of the Jack army and escaping as Hon-Maru is consumed by a massive explosion that sends Heihachi flying into a distant graveyard. From a nearby plane, a man in black watches and reports into his radio: "Heihachi Mishima is dead." News of his death spreads across the globe, and most assume it spells the end of the Mishima Zaibatsu — but behind the scenes, someone else has quietly seized control, and business carries on as usual. A month later, the King of Iron Fist Tournament 5 is announced.