Using his transmitter, Zone Fighter informs his father that he will battle King Ghidorah on Jupiter. Unfortunately for our hero, the space dragon had discontinued its pursuit. By the time Zone Fighter arrives back on Earth, Hikaru finds his house devoid of life. As it turns out, the Garoga had taken the opportunity of the downed Proton Barrier to kidnap the entire Zone Family and were now holding them hostage in their secret base. Wasting little time, the young man transformed into his human size Zone Fighter form and, with the Mighty Liner, scanned for energy readings that would lead him to the aliens base. Attacked from the ground by the Garoga Car, Fighter knew that he was close. Landing the car, he took off on foot to battle the soldiers manning the cannon equipped vehicle. Through superior fighting skills, the Peace Warrior prevailed and made his way into the underground base just in time to free Zone Great from a torturing device. Following that, he freed his brother and sister whom dealt with the remaining Garoga.

After the battle's conclusion, Hikaru returned the Proton Crystal to his grandfather. The family had little time to celebrate before the car’s alarm went off, alerting that King Ghidorah was about to strike again. Miles away, the space demon was defying gravity and holding cars in midair with its own power. Uttering Zone Double Fight, Hikaru transformed into Zone Fighter and plucked the citizen filled cars from the sky to return them safely to the ground. After this feat, the universe's only hope once again began his endless war against the energy spewing beast. Hurtling bolt after bolt, the humanoid giant was thrashed nearly to death. Junior and Angel, watching from the sidelines, stepped in with Smokey and blasted King Ghidorah away, but it was too late. Having no strength left and nearly blinded, the monolith hero was returned to human size. Badly weakened, his brother and sister flew him away in the Smokey vehicle just in time, as the golden beast unleashed its hate upon the research building.

Back at home, Zone Great restores Hikaru’s vision. Once finished, he takes the family to a secret room beneath the house where he shows them the Pandora Capsule, a interstellar aircraft original designed to take the family home to Peace Land. The machine was only capable of one more trip, because of its depleted power. If they used it to fly Zone Fighter into space, then they would never be able to return home. It was then that the family realized they were Earthlings, and that Earth was their home. Casting aside thoughts for their own safety, the family took the Pandora Capsule and battled King Ghidorah with Zone Fighter in outer space. Blasting the dragon with a few proton beams, they were able to force it to land with Zone Fighter on Jupiter’s surface. The heavy gravity of the planet would allow Zone to have the upper hand, as the demon would not be able to use hurricane force winds. Unleashing power after power, Zone Fighter attacked with unseen determination. The yellow scaled leviathan was helpless and soon was called into retreat by the Garoga. Confident the monster would never return, the family and warrior returned back to Earth, their now permanent home.