The Osugi family are aliens living together on earth. The father Shigeichiro Osugi is a weather forecaster from Mars, Iyoko, the mother absorbed in her weird water business, is from Jupiter, the son Kazuo is a freeter from Mercury and the daughter Akiko is a college student from Venus, with a complex about her beauty. One day the family realize that they have to save mankind from nuclear weapons that will destroy the world.