For many a young actor, there seems to be nothing more exciting than to go gritty, to put on a cheap accent and some eyeliner (gender depending usually, but not always) and get all serious and low-class. Blake Lively, the straight-A beach princess who stars on Gossip Girl, seems to be one of those young actors, as evidenced by her desperate, squirming work in the otherwise believable The Town and now her turn as the weed-addled girlfriend to two pretty California drug dealers in Oliver Stone's Savages. In the film, Lively is O, short for Ophelia, an earthy (or Lively's approximation of earthy) young woman who spends lots of time tangled up in bed (or on a chair, or in a tub) with Aaron Johnson and Taylor Kitsch, and chained to a couch in a Mexican drug cartel's kidnap bunker. She also narrates the film, all dazed-poetic mumbling, setting a strange tone for a hyper-violent movie about the messy futilities of retribution and the war on drugs. It's a dream role for an actress like Lively who is trying to grit herself up, but her efforts are sadly in vain.

Lively is cursed with an earnest voice and completely undangerous beauty. She'd maybe feel more at home in slicked, wavy hair, wishing a nice boy off to WWII or something. In Savages, which is based on the novel by Don Winslow, she's stuck trying to sell awkward lines like "I have orgasms, he has wargasms" and using terms like "the slammer." (A phrase perhaps better suited to this fantasy 1940s love drama I'm envisioning.) She's trying, but it just doesn't connect. This could be said of much of the rest of Stone's film, which is either a B-movie that occasionally explodes and splatters into moments of greatness, or an A-movie that should have set its ambitions a little higher. But for the sake of holiday-week goodwill, let's assume it's the former.

With Savages Stone returns to the scuzzy, saturated, chaotic aesthetic of 1997's U Turn, a nihilistic clutter of screwball violence and effortful seediness. But instead of irradiated small-town Arizona, Savages unravels in dreamy Laguna Beach and points south, making effectively troubling use of the jittery aura of drug trade madness that surrounds, and in some cases funds, some of California's wealthiest enclaves. Kitsch and Johnson are Chon and Ben, two toned and handsome young weed growers and distributors who have perhaps become a bit too successful. They live in a gorgeous beachside house, they've got the best kush and the hottest girl, but they're on the map now, and a cartel from Baja has come a'knocking, looking to partner up. It's not exactly a request. Ben is the Berkeley-grad businessman botanist while Chon is the Iraq/Afghanistan-haunted ex-soldier enforcer. Chon is hotheaded, Ben is rational, and quickly that complement turns into a liability. They refuse the cartel's offer, Chon offending them in the process, and plan to flee town. But the cartel's leader, Elena (Salma Hayek), and her chief muscle, a grinning psychopath named Lado (Benicio del Toro), are hip to their plan, and so kidnap the guys' shared girlfriend and threaten unimaginable torture should the bros refuse the partnership again.

Things go even screwier from there, with an increasingly large snarl of lies and double-crosses filling the frame. Chon and Ben are restless and want their girl back right away, whatever means necessary. Lado is dissatisfied with Elena, who is quickly losing money and men and soon an all-important election. And John Travolta's slimy DEA agent Dennis seems to be playing numerous sides at once. What this all adds up to is a satisfyingly entertaining jumble of a movie that's one part bracing action thriller and one part anarchic comedy. The stakes never feel all that high in Savages, not when O is painted, in one strange scene, as an irksome, clueless bimbo, not when del Toro keeps oscillating between arch comedy and suspenseful menace, but it's an exciting ride nonetheless. There is certainly more to be said about cartel violence — an ever-increasing, mind-boggling terror in Mexico — but I suppose this just isn't that movie. This is a dark, grimy romp, not an inquest into the current state of the North American drug trade. If you want to learn something, go watch Steven Soderbergh's Traffic (which, like Savages, features a scene of Benicio del Toro watching little league baseball).

The film is not without its lessons, though. Chiefly, the younger trio could learn a thing or two from their acting elders. While Johnson, Kitsch, and Lively exhaust themselves trying to seem tough, narrowing their eyes and lowering their voices (Johnson is a far better performer than the other two, but he still struggles here), Hayek, del Toro, and Travolta walk away with the movie with smirking brio. Travolta is a perfectly venal, sniveling slickster — he negotiates for his own gain with equal parts fear and cockiness. And del Toro, who makes himself about as ugly as possible in the film, mullet and all, is a giddily chilling monster. But it's Hayek who truly elevates this guttural film to a higher plane. Her crime boss (she inherited the business from her murdered husband and sons) is an empathetic mother figure one minute and a hissing pit viper the next. Hayek, sporting a harsh, blunt hairdo and gleaming white pantsuits, is an elegant, mannered villainess, one whose Spanish-laced fury is certainly scary, but nowhere near as terrifying as the way she eats a lambchop, all exacting, purposeful carnivorousness. She does great work here, and it's a performance I hope the Academy remembers come Oscar time. Seriously.

Savages is perhaps best looked at as an antidote to all the relatively kid-friendly fare that's doled out in the summer. Sure Prometheus tingled with R-rated gore and anxiety, and Total Recall will be a three-boob blast, but Savages is terrestrial and sinewy smut for grownups who want a titillating, if ultimately empty, thrill this season. Pretty young hardbodies do it to each other, brains and other bits are sent splattering, and some bad guys say some neatly frightening things. The end is an eye-rolling copout and Lively's narration tends to frustratingly sand down a lot of the film's nice edges, but you could do a lot worse when looking for a stylized crime spree. The ultimate message of the film is that everyone's a savage, heroes and villains alike. Even you in the audience watching this gunky thing. And if that's the case then, hey, might as well enjoy it.