Son Goku is the greatest hero on Earth. Five years after defeating the demon king Piccolo, he grown up and had a family--he married, and he has a child, Son Gohan. But what is the real reason for Goku incredible strength? A visitor from outer space arrives bearing terrible news--Goku is an alien, and the visitor, Raditz, is Goku brother! When Raditz turns out to be a ruthless killer, Goku must fight his incredibly strong brother to save his family and the entire human race. A surprising alliance may be Earth last hope: Goku will team up with his old enemy Piccolo-archenemies united to save the world!