Minato Kiyomizu wakes from a coma following a car accident. Though once a water polo star in junior high, he's lost three whole years of memories. Abandoning any hope of playing again, he enters Yamanami High School an entire year late.

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."

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.

With one month left till the prefectural tournament, Minato directs the others on how they should train while starting a regimen of his own to work on getting his groove back. He and the team have a lot on their minds as the days dwindle down.

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.