The Godzilla vs Kong ending leaves both Godzilla and Kong in new places in their stories, thus allowing both to coexist in future MonsterVerse movies. First announced way back in 2015, it's been a long journey getting Godzilla vs Kong onto the big screen, which marks only the second time the two iconic monsters have come to blows in a film, with their first bout being in 1962's King Kong vs Godzilla.

Warner Bros. and Legendary Entertainment's idea was that Adam Wingard's film would be the crowning installment of the MonsterVerse franchise, which began with Godzilla in 2014 and continued with Kong: Skull Island in 2017 and Godzilla: King of the Monsters in 2019. And the entire time, the studios promised that one of the Titans would win, which presumably would've left only one alive. However, Godzilla vs Kong takes steps to ensure that not only did Godzilla and Kong both survive, but they also had future stories set up by leaving their endings somewhat open.

Related: MonsterVerse: Godzilla/Kong Movie Timeline Explained

By combining aspects from all three previous movies - the Hollow Earth and Skullcrawlers from Kong: Skull Island, everything Monarch learned about the Titans in Godzilla, and Ghidorah's head and Godzilla's Alpha status from Godzilla: King of the Monsters - Godzilla vs Kong acted as the culmination of seven years worth of storytelling. After two fights, a team-up against Mechagodzilla, and the discovery of the Hollow Earth, Godzilla vs Kong ended with a promising outlook that made both monsters kings of their own worlds.

Hollow Earth Explained

Kong in Hollow Earth

Before the world discovered the existence of monsters, a senior official from Monarch, William Randa, postulated the theory of the Hollow Earth. While he and Dr. Houston Brooks are credited with confirming the theory in the MonsterVerse, particularly in the film Kong: Skull Island, the idea of the Hollow Earth began centuries ago in real life. English scientist Edmond Halley put forth the idea towards the end of the 17th century, and although it was disproved shortly afterward, the concept gained a foothold in science fiction and fantasy; notably, stories like Jules Vern's Journey to the Center of the Earth made great strides in expanding one's imagination of what the planet's interior would look like if the Hollow Earth truly existed. The MonsterVerse has its own version in Godzilla vs Kong.

As proposed by Monarch, the Hollow Earth is an open world deep within the earth that is connected by a series of tunnels or caverns that allow Titans to travel around the world at incredible speed; in Godzilla vs Kong, Dr. Nathan Lind says they travel approximately 1,000 miles in just two seconds. It's believed that the Hollow Earth is where the Titans originate, hence why so many monsters are alive down there that aren't on the surface, like the Nozuki and Warbat species. And based on the throne Kong sits upon, his axe, and the Godzilla-shaped skeleton in the ground (seemingly consisting of other axes with dorsal spikes), it seems Kong's ancestors were the rulers of the Hollow Earth.

When Randa and their U.S. military escort arrived on Skull Island in 1973, their charges confirmed their suspicion of the Hollow Earth. Then, a submarine in Godzilla: King of the Monsters took Dr. Serizawa and several other people through one of the tunnels to an ancient underwater city, which is believed to have been Godzilla's home. Godzilla vs Kong takes things further by having Monarch travel through the entry point in Antarctica into the actual Hollow Earth world. Not only is it Kong's home, but it's also a place that's survivable for humans as well.

Related: Godzilla vs Kong's Ancient Titan War & Myths Explained

Ancient Titan War & Kong's Axe

Godzilla vs Kong Axe Poster Header

First hinted at in the credits for Kong: Skull Island, Godzilla and Kong were born enemies; their ancestors fought an ancient war thousands of years before the events of the MonsterVerse films. According to what's shown in the Hollow Earth - the fact that Kong wields an axe made up of one of Godzilla's dorsal spikes and that there was a Godzilla-like shape in the throne room - it seems Kong's ancestors won their ancient war. That's perhaps why Godzilla's home was the underwater city and not the Hollow Earth, and why he already existed on the surface. Furthermore, the throne Kong sits on is one his ancestors must have sat upon as well, reigning over the monster kingdom.

It's in that room that Kong finds his axe, one that is powered by an old dorsal plate from Godzilla's ancestors, and the axe's hilt is also from a bone of another enemy, though it's unclear which one. By placing the axe - particularly the dorsal spike - in line with the Godzilla shape in the ground, the axe is powered up by the radiation from the planet's core (the axe-filled skeleton charges up its Atomic Breath in the same way Godzilla does). Godzilla's species feeds on radiation as a food source; according to Dr. Graham in 2014's Godzilla, it's why Godzilla and other monsters retreated to the ocean's depths as the Earth's radiation subsided on the surface.

Interestingly, there two aspects to Kong's axe, one of which helps save both Kong and Godzilla at the end of Godzilla vs Kong. Not only can the axe block Godzilla's Atomic Breath, but it can absorb the power (read: radiation) from it as well, thus allowing Kong to deliver an explosive Atomic Breath explosion upon impact. Kong uses it to disorient Godzilla in their Hong Kong battle, and Godzilla later specifically powers the axe so Kong can defeat Mechagodzilla as well. While Kong has used spears before - both in Kong: Skull Island and Godzilla vs Kong - it's the axe that sets him apart from other monsters, thus allowing him (and his ancestors) to conquer the Hollow Earth.

Jia's Connection With Kong

Like in Kong: Skull Island and Godzilla: King of the Monsters, Godzilla vs Kong also has a character who shares a connection with one of the titular monsters. In this film, it's Jia, an orphan who was taken in by Dr. Ilene Andrews after the Iwi - the native people seen in the movie Kong: Skull Island - were killed on Skull Island. Dr. Andrews says Jia's parents were killed in "the storm," presumably referring to the wild storms produced by Ghidorah in Godzilla: King of the Monsters, which destroyed countless cities and regions around the world. At some point after that, Jia was taken in by Ilene, who heads Monarch's facility on Skull Island.

Related: Why Godzilla Movies Struggle So Much With Human Characters

Remarkably, during her time on the island, Jia taught Kong to sign - and to a great extent, seeing as he understands when she tells him his family might be inside the Hollow Earth. Just like with past incarnations of King Kong, the MonsterVerse's version of Kong is quite protective; he's willing to fight anyone in order to safeguard Jia. But instead of having an unspoken bond as in other films, Kong and Jia can actually communicate. And their connection is amplified by emotion; there was a time when they were both alone in the world, longing for a family they no longer had. They became attached to each other, even when Dr. Andrews and Monarch took in Jia.

Apex Titan Plan & Hollow Earth Energy Source

APEX and Kong in Godzilla vs Kong

The human villain in Godzilla vs Kong is the group Apex Cybernetics, a company whose goal has been to topple Godzilla as the King of the Monsters. When the world at large first became aware of Godzilla, they had no way to combat him; Monarch themselves didn't know what to do. It's why the military began developing the Oxygen Destroyer, which was deployed against Godzilla and Ghidorah in King of the Monsters, though it was unsuccessful in killing the latter. So taking a page out of the Heisei era's Mechagodzilla II story, Apex created their own robotic Godzilla to counter the Alpha Titan and protect humanity from Godzilla's terror.

Part of their plan required a unique energy source Apex believed was located inside the Hollow Earth, but they had no way of getting there, partly because they couldn't locate the right entry points and because anyone who went inside never came back. Dr. Lind was recruited to help Walter Simmons and Apex get there by using Kong as a guide and Apex's HEAVs - specially-designed aerial vehicles that could withstand the Hollow Earth's gravity field pressure - but the problem was Kong's willingness to leave Skull Island and go into the underground world.

Apex and Simmons weren't interested in the Hollow Earth itself; they couldn't care less what the monsters - and Kong - did beneath the surface. Rather, they wanted the energy source that came from the Hollow Earth, the radiation that helped charge Kong's axe in the throne room, in order to push past the hurdles that were holding back Mechagodzilla. While Ren Serizawa - the son of the late Dr. Serizawa - was successful in interlinking with Mechagodzilla, the mech couldn't be "Godzilla's superior" until that energy was utilized. But the problem was, that energy had other effects as well.

Related: The Best Monster Villains For Godzilla 3: Gigan, Destoroyah & More

Mechagodzilla Origin & Ghidorah Head Connection Explained

Mechagodzilla appears in final Godzilla vs Kong trailer

As with many Toho monsters, there have been multiple versions of Mechagodzilla over the years, with the MonsterVerse's iteration taking inspiration from various sources. In this universe, Mechagodzilla was created by Apex Cybernetics - its power resembling the tech used in Apex's HEAVs - but the key ingredient in making the robot version of Godzilla work was Ghidorah. In the King of the Monsters post-credits scene, Alan Jonah was seen acquiring one of Ghidorah's severed heads; at the time, it was unclear what he had planned, but in the since the events of that film, Walter Simmons and Apex Cybernetics took control of the head and used it to create Mechagodzilla.

Ghidorah's uniqueness comes from being a three-headed dragon in which each head could telepathically communicate with the other. By tapping into that power - into Ghidorah's neural pathways - Ren Serizawa was able to control Mechagodzilla from afar, without actually being inside the giant robot. Furthermore, the design itself was modeled after Godzilla or, at least, one of Godzilla's ancestors. And coupled with Apex Cybernetics' tech, Mechagodzilla's powers and arsenal rivaled that of Godzilla's, including having its own version of his Atomic Breath - in many ways, this Mechagodzilla, again, heavily resembles the one from the Heisei era. However, there's also a hint of the Showa era Mechagodzilla, with the monster having a blade - in this case, a mechanical drill - at the end of its tail.

Who Was Controlling Mechagodzilla?

Mechagodzilla appears in final Godzilla vs Kong trailer

After Maya Simmons sent up the sample signature of the energy source from the Hollow Earth, Walter Simmons and Apex quickly began to replicate it. And because Godzilla was already in Hong Kong searching for the Mechagodzilla threat, Simmons forced Serizawa to incorporate the energy source into Mechagodzilla without first testing it. While it certainly helped Apex overcome the mech's drawbacks, the integration wasn't without issue. By combining the Hollow Earth energy source with Ghidorah's severed head, Ghidorah's consciousness awoke and electrocuted Serizawa. Then it killed Simmons with a physical strike. That primordial energy source was the final element in reviving Ghidorah - or, at least, the dragon's mind, to a certain extent. Although the initial test against the Skullcrawlers saw Mechagodzilla being controlled by Serizawa, in the final battle against Godzilla and Kong, Mechagodzilla was really Ghidorah the whole time, thus giving audiences a King of the Monsters rematch... with Godzilla's powers.

Godzilla Or Kong? MonsterVerse's New Alpha Titan

Early reviews for Godzilla vs. Kong are in

Godzilla and Kong's first fight in the ocean was unfair, to say the least. Kong was sedated and chained for most of the journey to Antarctica and he wasn't in his natural environment; whereas Godzilla was on his home turf. In the end, it was Monarch's decision to have Kong submit to Godzilla so that the rest of the fleet wouldn't be destroyed. (They did this by turning off all of their engines so that Godzilla wouldn't feel threatened.) But when Kong claimed his axe and powered it inside the Hollow Earth, Godzilla felt threatened again and attacked him using his Atomic Breath, breaking a hole in the earth. It ultimately led to their second and final battle, but the winner wasn't explicitly clear, despite what the movie's marketing material promised.

Related: Godzilla 3's Best Villain Would Be The One Monster He Can't Beat

According to Dr. Lind, Kong won the second round when the primate king used the Atomic Breath-charged axe to deliver an explosive blow against Godzilla, thus temporarily incapacitating the dinosaur. However, Godzilla regained his strength and took down Kong, with both monsters roaring at each other until Godzilla walked away without killing Kong - then later Kong dropped the axe in a show of acceptance. Taking that scene into account as well as Godzilla roaring after Mechagodzilla's defeat, Godzilla, for the first time, chose not to fight another Titan. Instead, he accepted Kong as being a second Alpha-level Titan - perhaps partly because he was impressed by Kong's warrior spirit and partly because Kong helped him defeat Ghidorah once and for all.

Kong Becomes King Of The Hollow Earth

godzilla vs. kong movie review

Godzilla vs Kong ended with both Godzilla and Kong retreating back to their homes; Godzilla went back into the ocean and presumably resumed his patrol around the world, while Kong went back into the Hollow Earth where Monarch had set up its latest research station. Given Kong regards the Hollow Earth as home now, he defeated the species that initially retaliated against him, and his ending scene, it's fair to say the MonsterVerse has now made Kong the King of the Hollow Earth, thereby giving him his iconic name of King Kong. Meanwhile, Godzilla is still the apex predator - the Alpha Titan - of the surface world. Godzilla vs Kong's ending has allowed both monsters to remain kings of their respective worlds without either of them infringing on the other. However, that doesn't mean they would never come to blows again; if one traveled into the other's domain, they may feel the need to defend themselves as they did in this film.

Next: All Godzilla/Kong MonsterVerse Movies Ranked, Worst To Best