Amuro gets trapped on an island where the only way out means choosing between a soldier's duty and protecting children who have no stake in this war. Cucuruz Doan exists in that impossible space, a man who's already made that choice, and now Amuro has to live with what it costs. The film strips away giant robot spectacle to ask what you actually owe to someone when following orders means abandoning them.

When a covert mission goes wrong, Mobile Suit pilot Amuro Ray and his comrades end up stranded on a remote island. Their unit had been sent to the so-called Island of No Return to sweep it of enemy forces, but instead they find a group of children and come under attack from an enemy mecha. Amuro must work out how everyone can get off this mysterious island, and along the way he meets a strange man named Cucuruz Doan. The mecha science fiction film retells the 15th episode of the original Mobile Suit Gundam television series, an episode left out of the show's English releases.