In the near future, much of the world has been forgotten at the bottom of the ocean due to rising sea levels. Natsuki Ikaruga, who lives in a small town surrounded and stranded by the sea, is invited by a mysterious woman, Catherine, to search for a treasure in his grandmother's house who was a marine geologist. One day, he dives to the bottom of the ocean in a submarine and encounters a mysterious capsule with a girl sleeping inside. The girl was a humanoid so sophisticated that she could be mistaken for a human.
Even though it's the city we all lived in.
رغم أنّها المدينة الّتي عشنا فيها جميعنا
Die Stadt, in der wir alle einmal lebten …
Y era nuestra ciudad.
Y era nuestra ciudad.
restera à jamais perdue
dans l’océan.
Un tempo ci vivevamo in quella città...
Mesmo sendo a cidade
onde todos nós vivíamos.
Город, где все мы жили…
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