El gladiador

Daiya Tsuwabuki is a boy in junior high who is known as the town liar. He claims that five years ago, he was saved by a large mechanical dragon when he and his father were attacked at sea by mechanical beasts. Even his mother and his only friend Naoto don’t believe his stories, but Daiya has physical proof of his experience, a mysterious device given to him by a young girl, a member of the mechanical dragon’s crew. Then one day, his town is attacked by two monsters, and the mechanical dragon, Daiku-Maryu, shows up. Daiya sees the girl who gave him the device years ago, and ends up in the dragon’s head, which transforms into super robot Gaiking, the Giant of Flame. Learning that he has control over the giant robot, he fights the enemy and drives them away from his town.

Daiya meets the crew of Daiku-Maryu, which includes Lulu, Gaiking’s supporter; Captain Garis; Vice Captain Rosa; Shizuka and Daimon in charge of the engine room; and Puria, the pilot of Stinger and the ace fighter of Daiku-Maryu. Puria does not yet accept Daiya and bullies him by beating him over and over in arm wrestling. Then suddenly the Demon Beast that they thought was already dead comes back to life and starts attacking the town again. Daiya, who becomes an official member of Daiku-Maryu, gets back on Gaiking and starts fighting the beast, and although he puts himself in danger because of inexperience, he manages to win with help from Lulu and Puria. Later, back on Daiku-Maryu, he learns that the enemy’s name is the Darius Army and that they come from the core of Earth.

Daiya learns that for their fight against the Darius Army, they have to go to the other world at the core of the earth, and Captain Garis gives Daiya some time to go say goodbye to his mother. Although his mother is relieved to see him alive, she is devastated to learn of his plans. While Daiya is still talking to his mother, he gets a call from Lulu, who tells him that Daiku-Maryu is being attacked by a Steel Beast. Puria comes to pick him up on the Stinger, and when they arrive on Daiku-Maryu, he jumps into its eye and onto Gaiking. After the battle, Daiya is upset that he has to leave his mother still heavy with grief, but feels encouraged when he sees her and Naoto standing on the shore to see him off.

In order to return to Darius, Daiku-Maryu must go through Death Cross Point and mend the subspace in order to prevent the enemy from going to the surface. The entry is an extremely harsh process, and Daiya, who is sitting in the Gaiking cockpit where the heat and pressure are worst, feels weak and nauseous. As they travel through the subspace, they run into a Demon Beast sent there by Saspazi, one of the four generals of the Darius Army. Since Daiku-Maryu is emitting energy to mend the subspace, it is not strong enough to counterattack the Demon Beast. Only Gaiking is capable of withstanding the heat, and despite the great danger of fighting in the subspace, Daiya takes Gaiking outside and manages to kill the enemy.

Daiku-Maryu arrives in Darius and goes to a regional city called Paltegona to stock up on food and supplies. Captain Garis orders Rosa to take Daiya and Puria into town with her in order to give them an opportunity to start getting along. In town, Daiya finds out that Daiku-Maryu and its crew are regarded as villains in Darius, a fact that has been bothering Puria for a long time. Daiya convinces her not to worry about what people think of them since it doesn’t change what they are there to do. Puria is impressed with Daiya’s way of thinking and opens up to him. On their way back to Daiku-Maryu, they are attacked by the enemy, currently under the command of Saspazi, who has no qualms about involving the citizens of Paltegona to serve his purpose. Gaiking, with support from other fighters, manage to drive the enemy away from Paltegona, but it does nothing to correct the misconception of its citizens, who believe that it was Daiku-Maryu who attacked their city.

Captain Garis temporarily assigns Daiya to five sections on the ship to decide which section he will join permanently. On the first day of the three-day trial, Daiya has a lot of trouble with the tasks of each section, especially when he has to run around Daiku-Maryu running errands for his bosses. But when he sees Lulu working hard at her job, he renews his determination and asks Shizuka of the Mechanic Team for advice. From the next day, he starts handling the tasks efficiently and even takes over for Lulu so she can get some rest. Then suddenly Daiku-Maryu is attacked by a Demon Beast, which breaks the Flare Tube, the passageway Daiya needs to get into Gaiking. But Daiya manages to get in by going outside the ship and jumping in through the eye. Using Rosa’s smart plan, Gaiking defeats the Demon Monster. Later, Daiya gets assigned to the Mechanic Team.