After spending their first year of high school in peace and quiet, Haruka and Makoto run into Nagisa, a new student who was a member at a swimming club with them when they were kids.  That swimming club is being torn down, so the three of them sneak in to dig up a time capsule that they buried in the back, which is when they are reunited with Rin, the fourth member of their group who left to study abroad.
that they used to belong to 
the same swimming club.
dass sie früher im selben 
Schwimmverein waren.
Pertenecían al mismo club de natación.
Pertenecían al mismo club de natación.
Ils étaient dans 
le même club de natation…
il fatto di aver frequentato 
lo stesso club di nuoto.
Antigamente todos eles faziam parte
 do mesmo clube de natação.
что они состояли раньше
в одном клубе по плаванию.