Marketing for Godzilla: King of the Monsters may have revealed the film's secret villains. Though King Ghidorah is of course Godzilla's primary adversary, it's a group of eco-terrorists who may actually be pulling the strings and causing the monsters to fight.
In the highly anticipated sequel to 2014's Godzilla, the alpha predator will have his hands full with the emergence of three more kaiju: King Ghidorah, Rodan, and Mothra. A clash between the four monsters (and possibly two more Titans) will threaten to ravage the planet and destroy all of humanity, which is what will cause the secret government agency known as Monarch to intervene in an effort to prevent needless destruction. While Monarch is trying to stop the violence and prevent more deaths, a second organization may be involved in the conflict as well, but may not be operating in the best interests of humanity.
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A new King Ghidorah action figure for Godzilla: King of the Monsters comes with an "Argo Jet." That particular aircraft has been spotted in several shots in the second Godzilla: King of the Monsters trailer fleeing from Rodan, and then flying toward King Ghidorah in the first Godzilla 2 trailer. However, it doesn't appear to be associated with Monarch, and it also isn't the name of any military aircraft. It's possible that the jet belongs to the film's real villains. It's been reported that Dr. Emma Russell (Vera Farmiga) and her daughter, Madison (Millie Bobby Brown), will be kidnapped by a "mysterious organization with their own plans for the creatures," which is presumably called Argo.
It's rumored that Argo consists of eco-terrorists who plan to use the Titans to punish humanity for the damage done to the environment. In the first Godzilla 2 trailer, Dr. Russell calls humanity an "infection" that's hurting the planet. It seems reasonable that Dr. Russell is being forcibly coerced into making this speech by her kidnappers. Dr. Russell has a way of communicating and perhaps even controlling the MonsterVerse's Titans, which could be the reason why she was kidnapped.
If this is indeed their goal, the Argo eco-terrorists of Godzilla: King of the Monsters wouldn't be the first humans to use technology to force the kaiju to fight on their behalf. This was also done in Godzilla: Final Wars, Godzilla vs. Monster Zero, and Destroy All Monsters. As for who could be the ringleader in all of this, Charles Dance's character is the most likely option. He's one of the few actors in the film whose name has been kept under wraps.
As for the Argo name itself - the meaning may possibly be linked to Greek mythology. Jason and the Argonauts sailed on a ship called the Argo to retrieve the Golden Fleece. The Argo ship was able to make the difficult voyage because it had been blessed by the goddess Athena. Some have claimed that the Argo was the first ship to ever sail. Its impressive history could at least explain the name of the Argo jet, especially if it's going up against something as powerful as a Titan. In turn, that would explain the name of the organization Argo as well, if the ship is their main weapon, so to speak.
It remains to be seen what these eco-terrorists will be able to accomplish or how much responsibility they hold for Godzilla's battle with all the other Titans in Godzilla: King of the Monsters. It may even be possible that they're the ones who find a way to awaken the Titans and send them on a collision course with each other.
