The second starring vehicle for Dwayne Johnson, known to fans of pro wrestling as The Rock, aims to be a modern “Midnight Run,” but it’s more reminiscent of Ernest Dickerson’s 1996 bomb “Bulletproof” (which was itself a ripoff of “48HRS.”). Johnson plays Beck, an enforcer for a mob chieftain called Billy Walker (William Lucking), but one with a decidedly soft side–he wants to quit the business and open a restaurant. Billy agrees to accept his resignation if he’ll first go down to Brazil and retrieve Walker’s wayward son Travis (Seann William Scott), a college dropout who’s tracking down ancient archeological artifacts. The job brings Beck into contact with a variety of colorful characters, including Mariana (Rosario Dawson), a sultry bartender with whom Travis is smitten; a group of curiously athletic rebels led by Manito (Ernie Reyes, Jr.); a comically daredevil Scottish pilot (Ewen Bremmer); and–most importantly–Hatcher (Christopher Walken), a sneering villain who’s enslaved the natives to work his huge gold-mining operation and is backed up by a private army of henchmen. Some nonsensical business involving an ancient tribal statue ultimately brings everything together. It isn’t long before Beck and Travis (and Mariana, too) are traipsing through the Amazon rain forest pursued by Hatcher and his crew, who want the artifact for their own dark purposes, and the two men, in the fashion the genre requires, are bickering their way to mutual respect and even friendship. Of course, there’s an inevitable raucous showdown between Beck and the nefarious Hatcher.

“The Rundown” represents a progression in The Rock’s cinematic career, but–quite deliberately–not all that much of one. It allows the star to go contemporary, setting aside the loincloth he wore and the sword he wielded in “The Scorpion King” for a suit and tie and some fine automatic firearms here, but the macho posturing hasn’t changed much. The picture is still basically a succession of big fight sequences strategically situated within a flimsy plot. It opens with the big fellow handling a whole passel of pro football players in a glitzy California night spot, and then, after some obligatory exposition, quickly follows that up with brawl in the Brazilian bar. It isn’t long before we get another set-piece, in which Johnson faces off against a small army of relatively petite jungle rebels. And even that will eventually be topped by the grand finale, in which he takes on all of Hatcher’s forces virtually single-handed. These eruptions of violence are decently staged and have some welcome comic touches, and they should certainly satisfy The Rock’s wrestling fans. Others, however, may find them all too familiar and, as such, a tad tedious.

The same can be said of the rest of the picture. The relationship between Beck and Travis feels like a rerun, and their banter is decidedly stale and unfunny. When the script does toss in an arguably new bit (as when the duo are confronted by some excited monkeys) it proves a bad idea indeed. And the picture fails to use Walken to best advantage. He’s an actor who could easily have created a memorably quirky villain (given the “Heart of Darkness” atmosphere of the character’s mining operation, the scripters surely missed a good gag when they failed to call him “Kurtz”), but here he’s allowed little more than a few of his patented screwball line readings. As for The Rock, he continues to show promise as a Ahnold-esque action figure without an accent (a position to which he obviously aspires, as a brief gag toward the start shows), and his experience in the ring allows him to handle the fight scenes dextrously; he also doesn’t take himself too seriously–a distinct plus. But the woodenness is still there. (Of course, that never stopped Schwarzenegger.) This is the second time around for Scott’s goofy sidekick–it’s essentially the same part he played in “Bulletproof Monk”–and once again he’s adequate but not nearly as boyishly charming as the producers hope and he obviously thinks. Dawson is photogenic if a little too sulky; it’s a pity that in the final reel she’s reduced to serving as the standard damsel-in-distress.

Technically “The Rundown” is very slick. Director Peter Berg and cinematographer Tobias Schliesser pull off a few impressively glitzy wide-canvas pans–one of Hatcher’s mine (complete with what look like thousands of CGI-created workers) and another an aerial-view jungle tracking shot–that show real visual imagination; there are moments when the montages resemble an outdoor version of the sort of thing “C.S.I.” does inside corpses. The Hawaiian locations, moreover, provide a lush stand-in for the South American rain forest. It’s too bad that in all other respects the picture seems such a rehash–a well-cooked one, perhaps, but a rehash nonetheless.