There's only one week left until the Prefectural swim tournament. But there's a problem; Amuro has lost one of the "X"s she wears on her head. Given to her by her grandmother, Amuro was warned that she was to wear them all the time and Amuro would be cursed if they were lost.
あむろと真綾という2人の新戦力が加わり、県大会に向けて気合が入る織塚。そんな織塚の号令のもとであむろが飛び込もうとした時、突風であむろの“ペケ”が片方だけ飛ばされてしまった。そのせいで元気がなくなってしまったあむろ。ウミショー水泳部は、競泳水着のまま、あむろの“ペケ”を追いかけて街へ向かい…。
Amuro ha perdido una de las cruces que le regalo su abuela y esta muy desanimada, todos sus compañeros del club de natación intentaran recuperar la cruz para que Amuro se recupere.
