Ryu Hayabusa-Ryu, the modern super ninja is the best friend of Kasumi's brother, Hayate. In the last tournament he successfully brought down Bankotsu-bo - the feared Tengu of Destruction - who brought chaos to the whole world. But before he allows himself to relax in a new era of relative peace, Ryu Hayabusa must enter the tournament again, this time to save the wrold from Genra, an evil being created by the DOATEC.