Professional wrestling hero John Cena probably said to himself one day, "You know what? I'm a big dumb guy. I bet I could play a big dumb guy in a movie." He mashed his fist on a telephone keypad, his agent answered, and thus was born "The Marine," a WWE-produced "Rambo" rip-off that allows Cena to flex his muscles. (His physical muscles, I mean. His acting muscles remain dormant.)

In this clumsy, dim-witted generic action caper, Cena plays John Triton, a Marine with cartoonishly large biceps who is discharged after single-handedly saving three soldiers from a cell of nine al-Qaeda terrorists in Iraq. Seems he recklessly disobeyed orders when he saved those guys, so the Marines want nothing to do with him. Back home in South Carolina, he takes a job as a security guard in an office high-rise but immediately loses it due to being a thuggish hothead.

(I am given to understand that in the wrestling world, being a thuggish hothead is one of Cena's most popular characteristics. I believe his fans will therefore find his "Marine" character quite to their liking.)

Then John and his wife, Kate (Kelly Carlson), are taking a road trip when Kate is accidentally kidnapped by a quintet of diamond thieves. (It's hard to explain.) John spends the rest of the movie pursuing them through a swampy river and its surrounding shacks and cabins, engaging in hand-to-hand combat where possible and only occasionally deploying such distasteful weapons as knives or guns.

The chief villain is a well-dressed psychopath named Rome. Played by Robert Patrick (and the movie does squeeze in a "Terminator" reference), he's the only enjoyable character in the film, simply because Patrick doesn't take himself seriously. He's actually enjoying himself, while everyone else is trudging through it laboriously.

Rome's accomplices include a hot woman (Abigail Bianca), on hand so the captive Kate can fight with her -- folks love a good chick-on-chick fight, you know -- a couple of all-purpose Movie Bad Guys, and a crazy, explosive-happy guy intended as comic relief. Unfortunately, the movie's idea of comic relief is for him to tell a story about when he was 13 years old and a camp counselor molested him. (Seriously.) He's one of the most singularly bizarre and ill-conceived movie characters I've seen all year, and I saw the Amanda Bynes movie.

John Triton, as burly as a gorilla but with less emotional range, has the following superpowers:

1. He can be inside a building when it gets blown up, yet emerge unharmed. This happens three times in the movie, with three different buildings.

2. He can be driving a car whose top half has been sheared off, leaving him with no protection whatsoever, and be shot at hundreds of times, riddling the hood and doors with bullet holes, yet sustain no injuries himself. The car's tires enjoy a similar bulletproofness.

But all superheroes have weaknesses, and John's is that if you hit him in the head with a fire extinguisher or a plank of wood, he will be rendered unconscious for as long as it takes you to escape.

The director, a first-timer named John Bonito, has allowed the fight scenes to be shot so darkly and edited so frantically that they're nearly incomprehensible. This method is usually employed to hide an actor's lack of fighting ability -- but John Cena IS a fighter. So why not let us see him actually, you know, fight?

It may be that the fight scenes were so choppily edited in order to avoid showing graphic violence and getting an R rating. Indeed, there are many instances throughout the film where it's obvious they've cut away from something before they wanted to. For as violent as the movie is, it's curiously blood-free.

Also, I like how John Triton runs and blows things up in slow-motion, but when he shifts gears in his car, it's sped up like it's the most exciting thing he's ever done.

Given wrestling's popularity, I'm sure there are people who will see "The Marine" just because it features John Cena. And those people will not be disappointed: The movie does, in fact, feature John Cena. John Cena is visible in nearly every scene. The one thing you can count on is that "The Marine," starring WWE titan John Cena, has ample quantities of John Cena in it. If you're looking for anything else, though, you might walk away a little unsatisfied.

(P.S. If you want to hear John Cena rap -- and I'm pretty sure you do -- stick around for the closing credits.)

Grade: D

Rated PG-13, a couple profanities, some mild innuendo, lots and lots of bloodless violence

1 hr., 33 min.