The series focuses on the survivors of planet Beal, which was wiped out by a mysterious entity known as Gaizok. The few remaining survivors escaped to Earth and split into three families, named Jin, Kamie, and Kamikita. While attempting to start a new life, the Jin family prepared for a Gaizok invasion of Earth by building three vehicles which when combined form the super robot Zambot 3.[1] While defending against Gaizok attacks, the Jin family also face harsh criticisms from the people they protect, who blame them for the invasion in the first place.