Mumei and the others are thrilled with a sudden pool day. However, their joy turns to horror when shadowy figures appear in the water. Sharks with plans of world domination? How can this be? With no possible escape, how will Mumei and the others cheat their way out of this new challenging test?
So long as I have this pen that matches 
Haku-chan's, I won't lose to anyone.
لن أخسر لأحدٍ طالما أمتلك
هذا القلم الذي يطابق قلم هاكو-تشان
Solange ich diesen Stift habe,
denselben wie Haku-chan, …
Mientras tenga esta pluma a juego con la
de Haku-chan, no perderé contra nadie.
Mientras tenga esta pluma a juego con la
de Haku-chan, no perderé contra nadie.
Si j’ai ce stylo
semblable à celui de Haku,
Ora che ho la penna uguale a quella di Haku-chan,
sento che niente può sconfiggermi!
Enquanto eu tiver esta caneta 
que combina com a da Haku-chan,