Natsuki sets his heart on creating a tidal power generator that utilizes the ebb and flow of the ocean's tides. He dives back into the ocean to find some materials and salvages some resin from the ruins of Ryuuji's family's factory. As soon as he gets back he gets to work. As they are working, Natsuki and Ryuuji exchange heated opinions over how the generator should be built. Atri intervenes and the two guys become closer friends. Meanwhile, a suspicious-looking character peeks at them from outside of the school....
If everything went as calculated, 
things wouldn't be difficult!
،لو سار كلّ شيء كما هو محسوب
!لما تعسّرت الأمور
Glaubst du, mich juckt’s,
was du berechnet hast?!
Ojalá todo fuera según los cálculos.
Ojalá todo fuera según los cálculos.
Dans la vie, ça se passe pas
comme sur les plans.
Stando ai calcoli, non c'è mai nessun problema!
Seria fácil se tudo sempre funcionasse
de acordo com os cálculos.
Ещё бы эти расчёты всегда работали!
Но мы не в сказке живём!