Even with an extremely low bar to clear, we still haven't gotten a good video game adaptation. Rampage comes closest, mostly by virtue of not taking itself too seriously, but it's still a miss.
The good news, as expected, is the Rock valiantly carries this ridiculous premise on his broad shoulders. Based on one of my favorite video games as a kid – but with more plot than this requires – Johnson plays Davis, a primatologist who has a close relationship with George, an albino gorilla he personally rescued from poachers. George gets exposed to a canister of an engineered chemical that fell to earth from a crashed space station, causing him to grow rapidly and display uncharacteristically aggressive behavior.
I was honestly shocked how the film develops the emotional connection they share in such a short amount of time. The motion-capture performance of Jason Liles and the special effects aren't on the level of the recent Planet of the Apes films, but it's not that far off.
The chemical that caused George to hulk out (and also modify a wolf in Wyoming and an alligator in Florida) was created by Energyne, your standard evil corporation, run by an ice queen (Malin Akerman) and her doltish brother (Jake Lacy). A former Energyne employee (Naomie Harris, slumming it) joins up with Davis to help him understand the chemical and how they might save George.
But George's mini-rampages at the wildlife sanctuary where he lives catches the attention of the U.S. government, particularly a shady operative played by Jeffrey Dean Morgan. He acts like he just walked in from a different movie entirely, specifically Sicario, since he's basically doing the same cowboy schtick Josh Brolin did in that much more somber film.
When Rampage works, it's not taking itself too seriously. Unfortunately, the movie seems to be at odds with itself over just how intense it needs to be. That was bound to happen with the movie's four credited writers, including Ryan Engle (The Commuter), the creators of the USA show Colony, and Adam Styzkiel (Due Date). That means the dialogue usually follows a pattern of passable human conversation, super-clunky exposition, then a B-minus quip. It also can't decide if it wants to be absurd and bloodless, or realistically violent. Some people get comically eaten whole just like in the game. But one scene, in which a black-ops squadron gets taken down by a mutant wolf, features a shocking amount of blood and entrails.
Ultimately, Rampage is too much of a mixed bag to fully recommend. The final 30 minutes or so is purely entertaining, both for fans of the game and monster movies in general. Yet most of what comes before feels too much like a game: serviceable-at-best dialogue, an abundance of set-pieces, and obstacles that only seem like filler. It's almost worth it to get to all the wanton destruction.