Filming of Dwayne Johnson's latest project, "Rampage," kicked off last week in Atlanta, and while little has been revealed about the adaptation of the classic arcade game, we do know it involves three mutated giant monsters that stomp across the United States, destroying cities and landmarks. But now that the action star has arrived in Georgia to begin work, he's ready to offer more information.

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In a new Instagram post, Johnson revealed the New Line film focuses on his character, who heads an anti-poaching unit in Rwanda, where his best friend is "a rare albino gorilla named George." After a group of "very bad people" use a serum to infect the gorilla, an alligator and a wolf, the three creatures grow in massive size and go on a "deadly rampage" to destroy the world. That, of course, leads to The Rock's character going on his own rampage in search of justice for what was done to George.

Goin' primal. ? Good to finally have boots on the ground here in Georgia for production of #RAMPAGE. I head up an anti poaching unit out of Rwanda. My best friend is a rare albino gorilla named, George. Very bad people infect George, an alligator and a wolf with a serum. All three animals grow at an unprecedented rate. Their size, speed, agility and violent aggression is off the charts. They go on a deadly rampage and want to destroy the world. George not happy. Me not happy. When animals like you, they lick you. When they don't like you, they kill you. I will hunt down the bad people who did this to my best friend. And when I find them, I will not lick them. We have the best VFX monster making team (WETA) on the planet. Our actors and crew have been working very hard to raise the monster genre bar. As always, let's have some fun. Let's shoot. ?? #PrimalDNA #George #Lizzy #Ralph #RAMPAGE

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Johnson also also teased monster effects by Weta, famed for its work on such films as "The Lord of the Rings," "The Hobbit" and "Godzilla."

Directed by Brad Peyton from a script by Carlton Cuse and Ryan Condal, "Rampage" stars Dwayne Johnson, Jeffery Dean Morgan, Naomie Harris, Malin Akerman, Joe Manganiello, Jake Lacy, Marley Shelton, PJ Byrne, Jack Quaid, Matt Gerald and Breanne Hill. The film arrives April 20, 2018.