Mild-mannered Aichi Sendou loses his Vanguard card to Katsumi Morikawa and chases him to gaming shop Card Capital.

Aichi, hoping to win his card back, learns the ins and outs of Vanguard while dueling Toshiki Kai.

Aichi's little sister shows up at Card Capital, worried about his activities; when Kamui Katsurago boldly issues a challenge to the shop's strongest fighter, Kai chooses Aichi to face him.

Shop assistant Misaki takes up Vanguard with Aichi's help.

Aichi's prospects to join the CF Research Club dim when the club members' poor grades threaten to permanently close down the group.

Aichi and his friends visit Kamui's old haunt, the card shop Voyage; Kamui disguises himself to avoid a battle with an old comrade he swore to defeat one day.