Warning! SPOILERS ahead for Godzilla: King of the Monsters.
In the climactic battle of Godzilla: King of the Monsters, Mothra dies protecting Godzilla from Ghidorah. Even so, she could still return in a sequel film. Legendary's MonsterVerse is only just beginning, and while 2020's Godzilla vs Kong is the only film officially announced, the studio is certainly interested in making more monster movies in their shared universe.
Godzilla: King of the Monsters is a sequel to the film that kicked off the MonsterVerse - 2014's Godzilla. That film was soon followed by Kong: Skull Island, a MonsterVerse prequel of sorts set in the 1970s which establishes not only King Kong but the remote island where he and other prehistoric monsters still live. Godzilla: King of the Monsters further fleshes out Legendary's MonsterVerse, introducing new Titans as well as their versions of classic Toho kaiju - Rodan, Mothra, and Ghidorah. In this film, these iconic monsters are changed a little to suit the story being told, but they are otherwise faithful adaptations of the characters fans know and love.
King of the Monsters' version of Mothra is very true to her earlier incarnations, remaining both a powerful but benevolent creature who only attacks when she feels threatened. In the film, Mothra is shown to not only be a mighty Titan in her own right, but a unique one in that she changes from a larva to an adult moth, cocooning herself while she makes the transition. Mothra is also seen sharing a symbiotic relationship with Godzilla, and it's in part thanks to the symbiosis that Mothra could return in a sequel like a Godzilla 3.
Mothra's Death Is Mysterious In Godzilla: King Of The Monsters
During the climactic battle of Godzilla: King of the Monsters, Mothra sacrifices herself to save Godzilla. That in itself is a noble gesture, speaking to Mothra's selfless nature, but it's more complicated than that. While at first it appears that Mothra is simply shielding an injured Godzilla from Ghidorah's devastating gravity beams, she's actually sacrificing herself in order give Godzilla the power necessary to defeat Ghidorah.
For those unfamiliar with existing Godzilla canon, what's happening at that moment in the movie may not be very clear. As Mothra's body disintegrates, a fine dust can be seen falling on to Godzilla. This dust is Mothra's energy, which she knowingly transfers to Godzilla in order for him to unlock a more powerful form - Burning Godzilla. Similarly to how absorbing the blast of a nuclear bomb helps Godzilla to recover more quickly from the Oxygen Destroyer, absorbing Mothra's energy gives him the necessary boost in power. When Godzilla arises, he is glowing red hot from all that extra energy, unleashing it at Ghidorah in multiple atomic pulses that rip the alien monster apart and killing him.
Godzilla simply isn't powerful enough to defeat Ghidorah alone, needing Mothra's energy in order to do so. In which case, Mothra's death may just be the most important moment of the whole movie. But is Mothra really gone for good?
A New Mothra Could Be Born In Godzilla 3
In the end-credits of Godzilla: King of the Monsters, there's a news clipping which reveals that a new Titan egg has been discovered. Might this be Mothra's egg? It very well could be seeing as there's a precedent for Mothra laying an egg before she dies. In the case of this film, if Mothra knew she might die in the upcoming fight against Ghidorah, then all the more reason for her to lay an egg beforehand.
Throughout Toho's Godzilla films, an adult Mothra dying and being succeeded by her offspring happens fairly regularly. Sometimes there's more than one Mothra larva born from the egg, though usually, only one reaches adulthood to become the new Mothra. Come Godzilla 3, it's entirely plausible that the egg revealed during King of the Monsters' credits will either hatch or have already hatched before the film begins.
Godzilla 3 could see a young, larva Mothra go into a cocoon and emerge as a beautiful giant moth, just as she did in King of the Monsters. Or, perhaps it will have already gone through its chrysalis transformation and from the start Mothra will again be in her adult imago form. Either way, the tease of an egg leaves the possibility for Mothra's return in Godzilla 3 wide open.
There Have Been Other Mothras Before
At the start of Godzilla: King of the Monsters, Mothra hatches from an egg being held at the Monarch facility, Outpost 61. The organization discovers the egg while excavating a site in the Yunnan Province of China - the Temple of the Moth. Inside the temple are carvings of a giant moth, illustrating how the people who built this temple worshiped the moth like a goddess. But if Mothra is only just hatching, who is the moth in the carvings?
Unlike Godzilla or Rodan - who are believed to be the exact same specimens that lived millennia ago - Mothra's life is cyclical. She hatches, enters her cocoon, emerges, lays an egg, dies, and is reborn. There have been other Mothras before, and there's no reason to believe that the Mothra who dies in King of the Monsters will be the last. Not only do we see Mothra live this cycle in the film, but the Temple of the Moth in China isn't the only place where Monarch has studied Mothra.
Dr. Chen reveals that her family have been Monarch employees for generations, sharing photos of her grandmother and grandaunt at an archaeological site relating to Mothra on Infant Island in 1961. This implies there could be many such sites dedicated to Mothra throughout the world. In which case, the Mothra to whom the Temple of the Moth was built is likely not the first Mothra, nor is the one Chen's grandmother and grandaunt studied on Infant Island. Mothra has lived many lives, and her time in King of the Monsters is only one of them.
Mothra Could Live Thanks To Godzilla
However, Mothra living on through her offspring and Mothra coming back to life aren't really the same thing. Or are they? Mothra doesn't simply die in King of the Monsters - she transfers her lifeforce to Godzilla. The film even has the atomic pulse Godzilla sends forth to kill Ghidorah briefly take the shape of Mothra's wings and her chirping is heard when he attacks. By doing this, King of the Monsters is again emphasizing the symbiotic relationship that exists between the two Titans, but it may also be hinting at how Godzilla could be the key to Mothra returning in Godzilla 3.
The fact that another Mothra egg has been discovered may not be all that's needed for Mothra to return. For her to be reborn, Godzilla may need to transfer Mothra's lifeforce back to the egg. This may, in fact, be something Mothra would typically do herself when nearing death, ensuring that once one cycle of her life ends, another can begin. In the case of her death in King of the Monsters, though, it would need to be Godzilla who transfers Mothra's lifeforce to the egg - which, also, may be something that's happened before.
While there's no specific evidence in the film to suggest this, it's certainly possible that part of Godzilla and Mothra's symbiosis involves the sharing of her lifeforce energy. This would mean that after Godzilla uses Mothra's energy to defeat a particular strong threat, he instinctually will seek out her egg to return Mothra's lifeforce. In doing so, he not only ensures that Mothra can live again, but that her energy will be available to him the next time he needs to defend his role as the Titans' apex predator and King of the Monsters.
- Godzilla vs. Kong (2020) release date: Mar 13, 2020