To shoot a promotional video for the Scar-red Riders, the group goes to the seaside town of Shonan. While away from their usual fighting, Kazuki tries to write a song, while Takt discovers an unexpected facet to Akira's personality.

Hijiri, a transfer student with a flirty attitude, makes sport of the other Riders. When Hijiri approaches Akira, Yosuke becomes mindful of her. While fighting an enemy with odd motives, Kazuki enacts a surprising plan.

As autumn sets in, Ryukyu LAG is caught up in the excitement of the school festival. The Riders practice for their first live concert and work to promote it. Akira and Hako strengthen their friendship. LAG gets an unusual visitor.