Minato learns from Chinu Kawakubo about a promise they made in the past. To fulfill their promise, he decides to join the water polo club, much to the delight of Eitaro Oka and the team captain, Jo Jojima. They utilize his fame to recruit members, but...

Takekazu Ejiri, Yutaka Babayaro Inomata, and Yoshiharu Ushimado join the club, but it needs one last person to make seven for a regulation team. They ask Shugo Amihama, who swam in junior high, but he refuses. When they persist, Shugo makes a proposal.

While watching a video, Minato sees his past self from before he lost his memories. When asked about it, Chinu reveals her motives for keeping quiet about the truth. After hearing what she says, Minato is shocked beyond words.