Nobita’s friends mock Nobita because Nobita is still Believe that there are heavens above the clouds.
Doraemon try to cheer him and using one of his Gadget, create a playgrund in the clouds.
Nobita, Doraemon, Shizuka, Giant and Suneo iscover taht there is indeed a heavenly World above the clouds where people lives.
Tha Cloud People is angry with human because human destroy the Nature and try to create a Noah Flood to destroy all human.