Cast
Alexander Skarsgård as Dr. Nathan Lind:A Monarch geologist and chief cartographer who works closely with Kong and charts the mission into the Hollow Earth. Skarsgård described his character as a reluctant hero who is "not an alpha, bad-ass" and "thrown into this very dangerous situation and is definitely not equipped for it." Skarsgård called Nathan an homage to 1980s films like Indiana Jones, Romancing the Stone, Lethal Weapon, and Die Hard. Skarsgård prepped for the film by researching the Hollow Earth, and learning American Sign Language to communicate with Kaylee Hottle.
Millie Bobby Brown as Madison Russell:The daughter of Monarch scientists Mark and the late Emma Russell. Madison believes there is a reason for Godzilla's erratic behavior, suspecting a conspiracy formulated by the Apex Cybernetics. She proceeds to investigate with Josh Valentine and Bernie Hayes. Brown described the film as a coming of age story for Madison, noting that the character has "grown-up" and become more "independent" since the events of the previous film, stating, "Her storyline has definitely evolved greatly in the way she deals with things, her attitude towards life, how much more stronger [sic] of a person." Producer Alex Garcia described Madison as the "advocate for Godzilla in this film" who tries to "vindicate" Godzilla and his reasons.
Rebecca Hall as Dr. Ilene Andrews:A Monarch anthropological linguist, and Jia's adoptive mother. Hall described her participation as "overwhelming" due to the film being her first project after her pregnancy, but found the experience "thrilling". Hall described Ilene as "the Jane Goodall of Kong".
Brian Tyree Henry as Bernie Hayes:An Apex Cybernetics technician turned conspiracy theorist and whistleblower aiding Madison and Josh to expose Apex. Henry described Bernie as a "crackpot" with a level of "heart" and "loyalty". Henry noted that the tragic death of Bernie's wife shaped him to become a conspiracy theorist with a podcast and further elaborated, "his goal is to use the tools at his disposal to bring the truth to the people. I always refer to Bernie as Anonymous. He can see the injustices, but no one really listens to him." Due to Bernie's protective nature of Madison and Josh, Henry jokingly likened Bernie to Brienne of Tarth.
Shun Oguri as Ren Serizawa:The son of the late Monarch scientist Ishirō Serizawa, and Apex's chief technology officer, who is the telepathic pilot for Mechagodzilla. Oguri described Ren's goal as trying to "protect the Earth"; however, the means to his goal differ from "everyone else, and his father." Oguri noted that Ren "sort of" followed in his father's footsteps but stated, "he doesn't believe he was heard by his father." Wingard stated that the character was underwritten due to a lack of time to explore the character and felt it was interesting to leave him a mystery.
Eiza González as Maia Simmons:A top-tier Apex Cybernetics executive, and Walter Simmons' daughter. González described her role as a "very smart woman behind a company". She described the film as "slightly comedic". González noted having enjoyed the fact that her character was a Latina woman with a high position within a company, and not forced into a stereotype.
Julian Dennison as Josh Valentine:A friend of Madison aiding her and Bernie to investigate the source of Godzilla's erratic behavior. Dennison described his character as a "nerd" and Madison as his "only friend". Dennison called Josh, Madison's "tech wingman", and the "realist in the duo", stating, "he kind of brings it, 'Oh, we shouldn't do that because we'll die.' And she's, 'No, it will be fine.' So, I think they play very well. And they're a very good mix of just craziness." Dennison screen-tested with Brown using scenes from Romeo and Juliet.
Lance Reddick as Guillerman:The director of Monarch. Reddick's role was originally larger, Wingard stated, "There was a scene earlier in the film, a big board room scene where they're setting up the mission. He had a larger role, but ultimately we didn't need that scene." He only appears in two brief scenes.
Kyle Chandler as Dr. Mark Russell:Madison's widowed father, Monarch's deputy director of special projects, and an animal behavior and communication specialist.
Demián Bichir as Walter Simmons:Maia's father, CEO, and founder of Apex Cybernetics, a tech organization invested in trying to solve the Earth's "Titan problem", secretly creating Mechagodzilla to exterminate them. Walter is a visionary entrepreneur and billionaire who wants to help humanity and make the world a safer place, but clashes with Monarch over their differing ideals on what is best for humanity. Producer Alex Garcia said Walter "has risen to a place… in the seats of power, and is wanting to help to stem and stop the madness and the destruction." Garcia stated that Walter is not necessarily a villain or a Machiavellian character but is "a very complex character who believes he's doing the right thing. And he may be, but that's where the mystery at the core of the film comes into play."
Kaylee Hottle as Jia:A young, deaf orphaned Iwi native who forms a special bond with Kong and is Ilene's adopted daughter.
Additionally, Hakeem Kae-Kazim portrays Admiral Wilcox; Ronny Chieng portrays Jay Wayne; John Pirruccello portrays Horace; and Chris Chalk portrays Ben. Allan Henry provided the performance capture for Kong, while animation supervisor Eric Petey provided Kong's full body performance and facial capture for the ocean battle sequence. Zhang Ziyi and Jessica Henwick were cast but did not appear in the final cut of the film, with Ziyi intended to have been reprising her role from Godzilla: King of the Monsters.
