Will the elementary school students become the main authority on the Earth's Defense? Class 5-3 is in the midst of a meeting to decide that. Thus far, only Jin Hyūga, pilot of Ken-Oh, is enthusiastic about it, but the weak-willed Kōji Hoshiyama and the rest of the kids can't hide their anxiety. Then the Chief of the Defense Force comes in and demands that the kids hand Raijin-Oh over to them. At that time, news of a Jaku Beast's appearance comes in. The police and defense forces are deployed, but their weapons are ineffective against it. Only those with the Raijin medals can defeat the Jaku Beast, and with everyone's agreement, Raijin-Oh deploys.