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...

Amihama stubbornly refuses to join, but a certain something changes his mind and Yamanami's Water Polo Club is officially underway. Despite the team struggling with the basics, they find themselves playing their first practice match.

Jo, the water polo captain, proposes that the team creates an original jersey. But emotionally attached to his own, Amihama declines saying, "I don't need a jersey."

Eitaro tries to persuade Minato to rejoin the water polo club. Wanting no part of it, Minato is frustrated at being compared to his past self and his failure to become Shogakukan's ace.

The Yamanami water polo club nervously faces the day of the prefectural tournament. Minato spearheads the team as they battle Rikka Gakuen in the first match, but their opponents have come up with a strategy to keep Yamanami from going on the attack.

It's finally time for their second match of prefecturals--the long-awaited showdown with Shogakukan. Minato, Eitaro, Jo, Amihama, Ejiri, Babayaro, and Ushimado join their seven hearts as one and challenge the best team in Japan.