Otto takes the form of the pilot and goes to his place, to the appointment with the emperor, together with Captain Future who pretends to be dead. As soon as the emperor enters the room, Future Captain jumps on him to immobilize him, but he soon realizes that it is only a hologram, a visual projection of the emperor. The latter then goes to the spaceship to execute the pilot, guilty of having failed the mission. Meanwhile, Future Captain and Otto enter the city of Jungletown and the latter, thanks to his ability to transform, is enlisted in the army to discover the emperor's plans. Here they discover citizens in the grip of the disease of regression, who after monstrous transformations become primitive men devoid of the use of reason. One of them attacks the beautiful Joan, but the girl is certainly not defenseless and with a karate move manages to immobilize the hominid. Joan Landor is the collaborator of General Quail (Captain Future meets her for the first time), who secretly gathers the high offices of the planet to talk about the serious disease that has struck the population. Joan accompanies Captain Future to the hospital-prison where the sick are collected and he is immediately struck by the girl's face, which reminds her of her mother's features.

Future Captain meets Commander Ezzle Garnie, his old friend, who invites him to go with him to the prison hospital located on an island surrounded by incandescent lava. Here, however, the emperor has already arrived who wants to free the ape-men in order to bring chaos to Megara. Future Captain and Joan, inside the hospital, are attacked by the ape men and Future Captain defends himself with his laser gun. The emperor deactivates the protective dome of the island and due to the lava, a serious fire spreads. Thanks to the intervention of the robot Greg, the dome is fixed and the ape-men are locked up again in the cells. Meanwhile, a strange calm reigns in the streets of Jungletown, the disease of regression seems to have diminished his infection and it seems that all the indigenous people of the planet have disappeared from circulation.

The Space Emperor has in fact gathered them on the planet Noon, to prepare them for an attack on the Earth base on Megara. The emperor warns General Quail and Garn of the impending attack and they ask Future Captain for help as their garrison is reduced to a minimum. The only possible operation is to capture the emperor. Little Ken ventures the hypothesis that the emperor is actually Kenneth Lester, a terrestrial scientist who went to Megara to study the Megara civilization. Based on that intuition, it is decided to go to the ancient city where Professor Wright's cyborg discovers that a man has left a signal indicating a distant point; the same direction that Lester took. This direction passes through lava falls, behind which an underground city hides. Here Captain Future and Greg find the scientist Kenneth Lester unconscious, who once recovered tells of having found a device capable of making his body almost incorporeal. After that discovery, Lester was attacked by a man with an iron mask who stole the device from him. Taken from the story, they do not notice that someone has closed the door from the outside. Lester owns a copy of the machine but it only works with robots, so Greg is instructed to dematerialize and go through the walls to free them. Meanwhile, the emperor of Space orders to attack the earthlings, but Captain Futuro and his crew are already on board the Comet and head towards Noon, strong in the secret on the emperor's weak point, rivaled by Kenneth.
This is just one of the many exciting adventures of Future Captain, later we will see him face the "guard" of the planet Sur un, Koom the sacred planet, the magician of the galactic circus, the winged men, the hunter of Bable, the forest of giant mushrooms and making hallucinatory journeys through other dimensions, in time and between overlapping universes.