Reki is a second-year high school student addicted to the highly secretive and dangerous skateboarding races held in an abandoned mine known as 'S.' Skateboarders are particularly obsessed with the 'subject' or the intense rivalries in the races. Reki takes Langa, who transferred from abroad to Japan, to the mine where the races take place. With no prior experience in skateboarding, Langa suddenly finds himself drawn into the world of 'S.'
