A gigantic cube appears in the air one morning above an airport and proceeds to absorb a passenger plane carrying 252 passengers. From within the cube emerges a being calling itself Yaha-kui zaShunina, an ambassador of sorts that wishes to communicate with and advance humanity.
Starting out as something like a mystery thriller heavy on technobabble, it eventually develops a few slice of life aspects before ultimately transforming into an action-tinged romance. Be aware that while in the prequel episode the characters are drawn in a 2D style, the majority of the show uses 3DCG.
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