In the present, Calvin feels he's never lived up to his once-promising potential and works as an accountant where his former assistant has been promoted ahead of him. Maggie is looking forward to attending their high school reunion, but Calvin doesn't want to go, viewing himself as a failure. And then out of the blue, he gets a Facebook friend request from someone named Bob Stone, who then reveals he's actually Robbie. When the two meet, Calvin is shocked to see the physical transformation as Robbie/Bud is now an imposing, muscular guy, still as nerdy as ever but able to dispatch some adult bullies with ease.

Knowing Calvin is an accountant, Bud asks for his help with an online financial account, and Calvin is shocked by the numbers showing up on his screen. But he's even more shocked the following morning when steely FBI agent Pamela Harris (AMY RYAN) and her two armed assistants arrive and tell him that Bud is now a rogue agent wanted for treason and the murder of his former partner, Phil (AARON PAUL). Calvin can't believe that and tries telling Pamela that they're not close friends. But the accountant then finds his life turned upside down as Bud keeps pulling him further into the case involving spy satellites, bad guys and such. From that point on, Calvin tries to figure out who to believe as things progressively get hairier.

Yet, part of me is curious whether it really is true that many who were the most popular in high school peaked then and have been on a downhill trajectory ever since, whereas the nerdy, awkward and often bullied geeks and non-modeling ready students have since blossomed and taken over the world.

That's part of the underlying theme of the mismatched buddy action-comedy film "Central Intelligence." It begins twenty years ago where a somewhat obese high school senior (Dwayne Johnson, or at least his head digitally composited onto the body of a younger man) is getting down to the grooves by himself in the school locker room shower.

Enter the school buddy and his friends who not only make fun of his name (part of which sounds like a particular part of the male anatomy) but also drag him from there, take him to a school assembly, and throw/slide him buck-naked across the gym floor, much to the delight and mean-spirited enjoyment of most of his fellow classmates.

That is, except for Calvin (Kevin Hart), the most popular student in school and the most likely to succeed. Rather than go along with the hijinks, he gives his humiliated classmate his letterman jacket to cover his front (and his pride), and the story then jumps forward in time to the present.

In the usual arrangement of such scenarios, the popular jock would be a jerk whose life after high school didn't amount to much, while the nerd would have ended up starting a software company and would now be worth millions with a gorgeous significant other.

Here, writer/director Rawson Marshall Thurber ("We're the Millers," "Dodgeball: A True Underdog Story") and co-scribes Ike Barinholtz & David Stassen have somewhat turned that usual scenario on its head. Calvin does indeed head downhill into a thankless job (although he married his beautiful high school sweetheart -- played by Danielle Nicolet), but he was never a jerk and thus doesn't go through the often expected comeuppance.

And rather than following the usual trend of remaining a nerd but one who made a fortune, Robbie ended up working out six hours a day for twenty years straight. All of which means his new alter ego of Bob Stone looks just like former professional wrestler turned actor The Rock, bulging muscles and all. While many might expect him to use his immensity to get revenge on those who wronged and bullied him in school, he's still a nerd at heart, albeit one who's a field agent in the CIA, and possibly a rogue one at that if his colleague (Amy Ryan) is to be believed.

The early parts of the film -- before the main storyline kicks in -- work surprisingly well from a sheer entertainment factor, with plenty of laughs to be had. And that mainly stems from the chemistry between Hart and Johnson, as well as the latter playing what's essentially just a big kid, and still a nerdy one at that, at heart.

But once the main story rolls around -- which isn't that complex (it revolves around a computer chip and surveillance satellites and Bob saying he needs to find that) -- the film loses some of its fun and laughs, as noted by the audience reaction at our promo screening. Yes, viewers (including yours truly) were still laughing, but not as much as earlier on as the mediocre story and okay but not spectacular action ended up suppressing the humor to varying degrees.

And while the bad guys finally show up in the third act, much of that action until then involves Ryan's agent trying to capture Johnson's and convince Hart's that his new/old buddy is actually the villain (something the film tries to do as well, although it's highly unlikely anyone will fall for that ruse). Having Johnson alternate between nerdy dweeb and heavily-muscled action hero doesn't also work as seamlessly as hoped, and since we've seen the actor do the tough guy action bit plenty of times, I was hoping for more of the goofy and charming portrayal.

Enough of that is present throughout to make the film work, with Hart doing his usual (but still amusing) frantic shtick. But with a little more thought, this could have been a far funnier and smarter action-comedy. As it stands, "Central Intelligence" is entertaining enough to warrant a recommendation and a 5.5 out of 10 rating.