What would you do if you suddenly found yourself in the middle of a war? Teenager Amuro Ray sees his life shattered when war comes to his home. During the chaos, Amuro finds himself inside the mobile suit Gundam, the Earth Federation's new secret weapon, and he somehow gets it to work. Amuro and the other refugees flee their homeland on the warship White Base. This group of children and inexperienced soldiers will change the outcome of the war.

Long ago, a powerful sentient robot known as GoLion, abused his great powers by attacking and killing creatures known as Deathblack Beastmen, boasting that no one could defeat him. For his arrogance, The Goddess of the Universe punished GoLion by separating him into 5 different lion robots. In the year 1999, a group of 5 young men returned to Earth after a space voyage, only to find it ravaged by nuclear war. After encountering the alien race known as the Galra, the 5 youths end up on the planet Altea and learn that the 5 lion robots that GoLion was split into are in hibernation in various parts of Altea. Somehow, they must reunite the lions and form GoLion, the only hope for the human race.