The film begins with a narration over shots of a modern-day Tokyo, noting that 16 years have passed since the end of World War II, and Japan has achieved rapid recovery.
Five ICBMs are eventually launched from both sides in the climax of the escalating war, with targets being major cities around the world including Tokyo, London, Paris, New York and Moscow. The Tamura family stay behind in the midst of the city's panic and hold a final dinner. That night, Tokyo is enveloped in a flash of nuclear light and blown apart, with the ground being torn asunder by the explosion and resulting in a violent volcanic eruption that almost completely consumes the wreckage of the city. Tamura and his family are killed by the detonation over Tokyo as their house is blown away by the ensuing fireball. Shortly after Tokyo is destroyed, the remaining four missiles strike their targets, obliterating all of them. The next morning after Tokyo's decimation, Takano's ship changes course to arrive at the remains of the destroyed city, prepared to die by the intense radioactive fallout. ..