After watching a Gunpla battle, Riku and Yukio decide to become Gunpla fighters, with Riku deciding to build a 00 Gundam while Yukio picks a GM III. With their Gunpla built, the two log into the Gundam Battle Nexus where they are met by Magee, one of the top ranked Gunpla fighters who also works as a Navigator to assist new players. Magee guides Riku and Yukio through a tutorial battle where they learn to control their Gunpla. After the tutorial, Riku receives a distress call and goes to investigate, finding an mysterious, unconscious girl who apparently has no memories of what happened to her...