‘Central Intelligence’
Director:
Rawson Marshall Thurber
Stars: Kevin Hart, Dwayne Johnson
Rating: PG-13
2 (out of 5) Globes

Ad-libbing can be a godsend. At best, it’s the movie equivalent of using every inch of the pig: It allows actors to do more than read lines. They help improve the material, creating a better whole. At worst it’s a lazy crutch. “Central Intelligence” is a high-concept action-comedy, pairing a suburban office drone (Kevin Hart) with a he-man super-spy (Dwayne Johnson). But it’s also a low-concept comedy, and that concept can be summed up as, “Eh, let Kevin Hart and The Rock do whatever.”

Thing is, there’s a promising idea here, if one so derivative it’s almost feels classical, like the fish-out-of-water comedy. In the grand tradition of “The In-Laws,” “True Lies” and “Grosse Pointe Blank” — a film from which “Central Intelligence” perhaps cribs most — it finds middle class types caught up in gunplay and intrigue. Hart’s Calvin was once the most popular guy in high school. Twenty years later he works at an anonymous desk job and laments his big, comfy house and long-sufferring but supportive wife (Danielle Nicolet).

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Then he reunites with Dwayne Johnson’s Bob Stone. Once an overweight nerd who was subjected to epic fits of bullying — via CGI that puts his face on a CGI body, an effect that will haunt dreams more than Johnny Depp in “Alice Through the Looking Glass” — he disappeared and re-materializes as a muscled golden god, though one still into unicorn tees and Facebook Messenger gifs. But he’s also a lethal CIA agent, and he’s either a deadly rogue on the lam from his superiors or a deadly nice guy out to clear his name.

Action is hard and comedy is hard, but doing the two together is harder than both put together. The laughs interrupt the thrills and vice versa. “Central Intelligence” tries to be a comedy with action, not the other way around, but there’s so much plot, so many hairpin turns, so much scowling from Aaron Paul (as a fellow agent) and so many shoot-outs that the actors rarely get a chance to cut loose. That’s a shame, since the scenes where they’re given room to banter appear to have been written as “TK Kevin Hart and The Rock just riff or whatever” in page-filling letters.

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And yet at least one of our stars look rushed and strained. Hart, an actor who seriously needs to stretch out his shtick, gamely plays against type, accepting the role of the straight man (who will have the occasional Kevin Hart-y hissy-fit). But he more often looks lost and even tired, unsure what his function is in a movie where he’s not supposed to always be overtly funny — where he’s selflessly given his co-star the best jokes.

Johnson, as expected, is game, and he delights in making Bob goofy-creepy. The hook is that you’re not supposed to be able to tell if he’s nuts-good or nuts-bad, and Johnson can get a lot of mileage simply rocking a grin that’s way, way too big for comfort. The filmmakers know he’s their ace in the hole, and it quickly becomes clear they assumed he’d smooth over any wrinkles and fill in any and all shortcomings. This is what happens when improv becomes too prevalent: writing becomes lazy because funny people, it’s assumed, will always be funny. But even when they are, as with Dwayne Johnson in “Central Intelligence,” it just makes everyone around them look like they’re not trying.

Follow Matt Prigge on Twitter @mattprigge