'Rampage' shows why The Rock is a global action star, but it's a dumb movie full of cliches

• "Rampage" is not good, but it shows why Dwayne Johnson is a global action star.
• Outside of some amazing CGI, he's the only reason to go and see this movie.

In many ways the adaptation of the video game "Rampage" is the perfect example of a Hollywood studio trying too hard to make a tentpole movie.

Here's the playbook: Use a game that's literally just about giant radioactive monsters destroying high-rise buildings and beef it up with CGI, sprinkle in a bare-bones plot to break up the action, and get a movie star who can get audiences worldwide to the theaters.

It's worked before, and with Dwayne Johnson on the poster, Warner Bros. hopes it can work again. But I think it's my duty to tell you that The Rock's latest movie is really, really dumb.

Johnson plays Davis Okoye, a former anti-poacher who is now the primatologist at the San Diego Wildlife Sanctuary. He loves working with apes - in fact, he prefers spending time with them to most humans - but there's one in particular he has the closest bond with. "George" is a rare albino Silverback gorilla that Okoye rescued as a baby when poachers killed his family. Okoye and George communicate through sign language, and have a good time busting each other's chops. Okoye has even taught George how to give the finger.

But their wonderful bond is tested when George is infected by a mysterious chemical that mutates him into a raging beast and makes him grow to an enormous size. And George isn't the only one. The same thing happened to a wolf in Wyoming and a crocodile in Florida. Turns out, they were all infected with a genetic editing substance created by the company CRISPR that crash landed on Earth (the chemicals were being tested in a space station … it's a long story).

Okoye teams with Dr. Kate Caldwell (Naomie Harris) to try to figure out what has happened to George and prevent him (as well as the wolf and croc) from causing damage throughout the country.

Brad Peyton, known best for directing Johnson's previous box office hit disaster movie ("San Andreas"), is at the helm and that should tell you what you're getting yourself into. Like that movie, "Rampage" is a CGI wonder with little plot and a whole lot of awful cliches and bad dialogue.

Unfortunately, it's the great Jeffrey Dean Morgan who is responsible for a majority of the latter. Playing Agent Russell (from the OGA or "Other Government Agency"), he can't stop reminding us that he's just a good ol' cowboy - and just in case you forget that little fact, he's sporting a silver belt buckle and a gun with a pearl handle. And we have to suffer through this talented actor having to say lines like, "Us ass----s have to stick together" and, "Whelp, you saved the world!"

But what sticks out for me as the worst part of the movie is a dramatic moment that becomes a total dud. It's nothing major to the story, but just shows how lazy it is. Okoye is shot by the evil CRISPR owner (played by Malin Akerman), leaving Dr. Caldwell all alone trying to stop the onslaught of monsters. But suddenly Okoye reappears, and when asked how he's still alive he literally says, "I guess it didn't hit any major arteries." And that's it! It's never addressed again, he goes on like he's never been shot in the gut.

All that said, Dwayne Johnson proves why he's making millions of dollars a movie.

Around all this awfulness - Oh, and Joe Manganiello is only in the movie for about five minutes - Johnson can still make you enjoy what you're experiencing. He's charismatic, funny, and gives a heartfelt performance across a CGI gorilla. Seriously, the best parts of this movie are when Okoye and George are on screen together. That's a testament to the CGI, which is really top notch.

So, the movie may be mindless, but if you're a fan of The Rock, "Rampage" is tolerable.

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