The film's story poses the possibility that all of humanity, without exception, live in two worlds of existence: the real world and a second world known as "Hem." Humans live their lives in Hem when they sleep in the real world. Hidden in each person is another life of which he or she has no recollection of, except for nightmares which are soon forgotten upon waking up. However, there a few rare individuals who are aware of the existence of Hem and the curious consequences it has on the real world.
Note: The actors and the director himself are seiyuus
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