A mysterious cloud descends on Tokyo, surrounding the city with a wall of turbulent clouds and electric interference that cuts off all communication. The fate of the millions of residents is unknown. Asakura, a scientist en route to Tokyo to visit family, finds himself detained and recruited to help study the cloud in hopes of finding a way to break through it. He befriends two reporters, Mariko and Yosuke, who assist him in his research. While the origin of the cloud is unknown, Asakura deduces that it’s composed of highly charged atomic particles existing in a stable equilibrium. Mariko, who also has family trapped within the cloud, berates Yosuke for his apparent indifference to the suffering of those cut off from Tokyo while reporting on the story.

Asakura devises a machine to puncture the cloud by disrupting the equilibrium and forcing it to dissipate. Two prototypes of the truck mounted magnetic emitter are produced. The first test ends in disappointment, as the cloud’s electric energy field threatens to destroy the truck before the emitter can reach effective range. As if in response to the test, the cloud swells and swallows up the surrounding suburbs, forcing everyone to evacuate. Asakura pilots one of the prototypes himself, attempting to breach the cloud with the emitter, but the cloud’s electrical energy thrusts his truck away and he is wounded.

Yosuke seeks to redeem himself to Mariko and takes command of the second prototype for his own kamikaze run at the cloud. He manages to push his truck further than Asakura and the emitter punches a hole clean through to the inside. Mariko and Yosuke hurry through the opening and find that the city’s inhabitants had survived under the cloud. The cloud dissipates and the evacuees return home.