Under anchor headquarters a year ago. Takimoto, Chigusa and others were following the whereabouts of Zero One, which was dazzling. Both Chigusa and Chigusa's buddy, Second, were brave enough to catch Zero One with their own hands. And Takimoto is worried about the two who are tied together by that strong bond. One day, Zero One attacked the Under Anchor.
一年前のアンダーアンカー本部。滝本、千草らは姿を眩ませたゼロワンの行方を追っていた。千草も千草のバディであるセカンドも自分たちの手でゼロワンを捕まえようと勇んでいた。そしてその強い絆で結ばれた二人を心配する滝本。そんなある日、ゼロワンがアンダーアンカーを襲撃した。
