From the UN rocket launch site the two-man rocket, Leona 3 is launched in order to solve the mysteries of the Milky Way Nebula.
Nambu leaves the launch site together with the president in a private plane, but then they are reported missing. The real president has been killed before the launch.
Suddenly, Leona 3 deviates from its course. The control mechanism in both the machine and the control center has no effect. As it stands, it seems that the rocket will crash on the Shaku peninsula, resulting in 20.000 dead and injured people. The Science Ninja Team is charged with the search for Nambu, who participated in the development of the control mechanism.
Nambu has been locked up in an atomic power plant on the Shaku peninsula. He gets in contact with a transmitter. Katse turns off the interfering radio waves on purpose, thus luring the Science Ninja Team there. Then he locks them up in the power plant together with Nambu. Telling them that Leona 3 will fall onto the plant, Katse escapes in a devil star disc plane.
They have a narrow escape from the power plant, however, since it is already too late to correct the course of Leona 3, Nambu orders them to shoot a rocket at Leona 3. The crew of Leona 3 is already prepared and has cut the connection as well. Ken is at a loss. However, when Joe wants to press the button, Ken does it.
Leona 3 disintegrates. Only the rosary, containing the last prayer of the crew, comes floating down towards Earth.