At an air show, a plane enthusiast tries out a simulator of the B-52 bomber. He is later approached by Pizza with a Zonder crystal. Elsewhere on the show grounds, Hana and Ayame climb into a physical B-52 on display. Its engines start up on their own and it takes off with the two girls in it. The Zonder appears in the cockpit and morphs the bomber into EI-21. Kazou who is attending the show with his younger siblings spots the Zonder and immediately runs to contact 3G. Mamoru who is out fishing with Sunou senses the Zonder and leaves to rendezvous with Volfogg. The 3G staff lifts down to the Big Order Room and discuss the new Zonder. They track it to a Defense Force base which it raids and absorbs a large supply of bombs and missiles from. Entouji calculates that it’s now heading right towards the Bay Tower. HyoRyu and EnRyu grab their Pencil Launchers, and Goldymarg wonders why he’s not being deployed yet. EI-21 begins carpet bombing the city, but HyoRyu and EnRyu fire adhesive at the warheads to stop them from exploding. 3G scans EI-21 and discover Hana and Ayame still stuck inside it, meaning they can’t attack it directly. Ayame is still oblivious to their situation while Hana clings to her in fear. Guy fuses with Galeon and engages EI-21 to try and rescue the girls. Mamoru wants to help, but Volfogg tells him to have faith in the 3G Mobile Corps and wait. Guy docks with the StealthGao and DrillGao. Pizza watches from afar and has another flashback to his past. Goldymarg contacts Hyuuma and demands to be deployed, but Hyuuma reminds him that he has a different purpose than the other 3G robots. Goldymarg refuses to sit around while the Zonder is right over them and busts out of his locker. He smashes a hole in the underwater tunnels and falls to the ocean floor, with the impact deactivating him.
EI-21 pelts Guy with missiles and anti-air fire as he tries to approach it. Goldymarg reactivates and changes into his Goldytank mode. He drives up to the surface and starts firing at EI-21. HyoRyu and EnRyu tell him to stop because the girls are still stuck in the Zonder, and Goldymarg accidentally drives over one of the warheads, setting it off. Goldymarg is completely unharmed and starts driving up the side of the Bay Tower to get closer to EI-21 despite Hyuuma ordering him to stop. Ayame straps herself and Hana into seats and tries to eject them but they don’t work. Guy breaks through the anti-air fire and uses the DrillGao to slice open the bomber’s top. The impact causes the seats’ ejection mechanism to finally work and the girls parachute safely to the ground. Goldymarg drives off the side of the tower and changes back to robot mode before grabbing on to EI-21. Volfogg and Mamoru head off to rescue the girls while HyoRyu and EnRyu launch LinerGao with their cranes towards Guy so he can perform Final Fusion. Goldymarg punches EI-21 and they both plummet to the city below. Taiga quickly has the Dividing Driver launched to avoid having them cause any damage to the city with their fall. EI-21 morphs to humanoid form while 3G frantically tries to reach Goldymarg. Guy fires a Broken Magnum at EI-21 but the latter destroys it, rendering Hell and Heaven unusable. EI-21 tries to bomb Guy but HyoRyu and EnRyu disable the warheads with their Pencil Launchers again, forcing it to shoot at them with its machine guns. Goldymarg gets up again and shoots EI-21 down. He combines with GaoGaiGar and they blaze past EI-21’s anti-air fire and perform Hammer Hell and Heaven. Amazed at Goldymarg’s resilience, Pizza leaves while Mamoru arrives to purify the core.
The point of this episode is more or less to show us that Goldymarg’s damn near indestructible, which is a good thing because his impulsiveness nearly cost 3G the battle if not Guy’s life. The only thing missing would have been a montage at the beginning showing 3G testing his armor by hitting, shooting and blowing it up with everything they got. On the other hand, I find it strange that the Machine Kings never thought to destroy GaoGaiGar’s right arm before Goldymarg debuted. That certainly would have put 3G in quite a bind back then, but here the threat barely lasted for thirty seconds before Goldymarg casually recovered from a 300 foot drop.