Here Comes the Boom (Sony Pictures)

Kickboxing, line dancing, krumping, parkour: As soon as something becomes popular, Hollywood has to find a way to stuff it into a movie. Mixed martial-arts fighting has been a little trickier to arrange; MMA fighters get cast in action movies all the time, and the documentary Fightville made some compelling arguments about the appeal of the form, but actually incorporating the sport into a narrative feature was seen as tricky.

But in the fall of 2011, Gavin O’Connor’s Warrior – with Tom Hardy and Joel Edgerton as brothers and MMA fighters on a collision course with one another – demonstrated that it was possible to make a movie about the sport with some complexity and emotional depth. Warrior didn’t last very long on the big screen, probably because it was perceived as just another action picture, but Nick Nolte’s subsequent Oscar nomination legitimized it by the time it came to disc, and it’s found a decent following since then.

I’m not a big fan of MMA myself, but I bring up Warrior to prove that it’s possible to make a good movie about any subject. And it’s fascinating to watch two of this week’s new releases, Here Comes the Boom and Alex Cross, try to incorporate the sport into their narratives. One kind of succeeds; the other definitively does not.

Weirdly enough, it’s the slapdash Kevin James movie, Here Comes the Boom, which works best. The latest throwaway comedy from Adam Sandler’s Happy Madison shingle – the production house that brought us James’ infantile Paul Blart, Mall Cop and Zookeeper – the whole picture seems to have been built on a four-word pitch: “Kevin James, MMA fighter.” And it turns out that’s all you need to make a movie.

Here Comes the Boom casts James as a science teacher who reluctantly signs up for an ultimate-fighting circuit in order to save his school music program and its lovable but clueless teacher (Henry Winkler) ... and maybe impress hot nurse Salma Hayek in the process. Absolutely nothing happens that you wouldn’t expect to happen in this sort of movie, but James is strangely credible as a middle-aged slacker finding his lost mojo while being beaten to a pulp over and over again. His combination of emotional accessibility and weird physical grace makes him entirely believable in the role, and that gives us a rooting interest in the fights.

That’s not the case in the week’s other MMA movie, Rob Cohen’s Alex Cross. In all fairness, calling Alex Cross “an MMA movie” is sort of like calling The Amazing Spider-Man a movie about the internship program at Oscorp; it’s just there to goose the plot along. Although even that’s a stretch, since the MMA sequence in Alex Cross (a) could have been replaced with any of a dozen different things and (b) doesn’t even involve Alex Cross.

Alex Cross, as you may recall, is the world-weary FBI profiler created by the author James Patterson and previously portrayed by Morgan Freeman in Kiss the Girls and Along Came a Spider. Cross’ return to the screen ignores those two films, rolling the clock back to the character’s formative years as a Detroit homicide detective and his pursuit of a psychotic assassin-for-hire known only as Picasso.

Now, the rules of every detective thriller demand the villain be introduced as an unstoppable badass, so Alex Cross introduces Picasso on the job, getting close to his first target by getting himself on the card at an underground MMA competition. We’re supposed to be impressed by the character’s fighting prowess as he takes out his much larger opponent, but all you’ll be thinking is: Wow, how long has Matthew Fox been starving himself?

Fox’ bug-eyed, emaciated performance is all sorts of insane, and not just in the service of the character. It’s as though the Lost star is doing his best to distance himself from the sympathetic, broken hero he defined so well on that show, altering his body and chewing the scenery to play a child’s conception of Eeeeevil. He does handle his fight scene fairly well, but the movie never requires him to display any sort of physical prowess again – probably because Fox so outmatches Tyler Perry’s hulking, wooden Cross that we’d never believe the good guy could beat him in close quarters.

Yeah, about that. Matthew Fox is kind of awful in Alex Cross, but he’s a mesmerizing kind of awful, so fully committed to a terrible performance that he reaches Nicolas Cage levels of watchability. Which only puts Perry further to shame, since he’s so unconvincing as Cross that you end up rooting for Picasso to win. It’d also liven up the tepid movie, which feels like it fell through a wormhole from 1994, the last time this sort of low-key cat-and-mouse thriller could hold an audience’s attention.

Maybe Perry should have gone up for Here Comes the Boom instead. He’d certainly have been more believable as a burned-out educator than he is as a genius FBI profiler, the poor sap. Although I guess he can soothe himself just fine with the profits from the next Madea picture. Meanwhile, think about poor Matthew Fox, who spent all that time in the gym for nothing.

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