Professor Saotomè leaves the center to go to an island where a meeting with the military forces of Japan is held in order to develop a plan to counter the enemy. Unfortunately the demons are aware of the scientist's movements and a captain of the demons, with an action studied in detail, manages to capture the professor and take hostage the occupants of the hotel where the meeting was held. The Getta Robot immediately intervenes on the place of the abduction and a Demon Robot makes him fall into the mouth of a nearby volcano. It is then Mikiru's turn to take action but in the meantime the boys have got out of harm's way thanks to Rygar's drill arm. After Ryo, Hayato and Musashi are able to disguise themselves as soldiers and free the professor and hostages. A long escape begins aboard trucks and vans as the demons do not give up but when they arrive at the shuttles, the Getta Robot is formed, to face the evil monster of demons on equal terms. The Getta comes out damaged by the fight but this time it is the monster that ends up in the volcano, being definitively destroyed.