In Neo Tokyo, disillusioned youth form tribes that battle each other in an intense game called Extreme Baseball. One night, two kids – Haru Shirogane and Taiga – meet the strongest XB Player Shun Kamiya. Haru and Taiga join Shun's group, the Minato Tribe, to play this cutthroat game against a mysterious man who has begun taking control of all the tribes. Can they defeat him before it’s too late?