With “Savages,” director Oliver Stone sets aside the highfalutin’ airs of his past few pictures (“Wall Street: Money Never Sleeps,” “W,” “World Trade Center”) and cuts loose with his idea of a fun summer movie — a lurid, fast-paced thriller about two California pot farmers whose mutual girlfriend is kidnapped by a rival Mexican cartel. This is the Stone of “Natural Born Killers,” “U Turn” and “Any Given Sunday,” a director whose flair for absurdist excess and merciless satire can turn off viewers of milder sensibilities.

But “Savages” is something those other movies were not: aggressively, defiantly stupid. Based on Don Winslow’s well-regarded page-turner (he also co-wrote the script), the movie has a propulsive energy that suits Stone well as he recounts exactly how Chon (Taylor Kitsch), an ex-Navy SEAL and veteran of two tours in Afghanistan, and Ben (Aaron Johnson), a college grad who majored in business and botany, built a marijuana empire that turned them into millionaires. Using surreal visuals and montage, Stone lays in the details needed to make you buy the movie’s central premise — that these two ordinary guys, with no connection to organized crime and no experience in the drug trade, became happy-go-lucky beachfront kingpins.

Those early scenes also introduce one of the film’s most unlikely conceits: the lovely, bird-brained Ophelia (Blake Lively), who prefers to go by “O” and lives in carnal communion with the two guys, letting them take turns with her in the sack, and sometimes just sharing her bed with both of them at the same time.

So when Ophelia is kidnapped by Elena (Salma Hayek), a Mexican drug lord who wants to force the gringos to share their profits, the guys resort to desperate measures to get her back. How else will they have sex? The title of “Savages” is meant as a bitter joke: Everyone in the movie, from Elena’s murderous goons (led by Benicio del Toro) to a crooked DEA agent (John Travolta) to the likable heroes, will commit extreme acts in order to get what they want. The war on drugs turns everyone into animals. That’s the only political statement Stone is out to make here, other than smoking pot is not necessarily a bad thing.

The rest of “Savages” is supposed to be pure, if brutal, entertainment, pulp fiction with an unusually graphic punch. Stone’s reliance on practical effects (real blood squibs, actual fireballs instead of CGI) is refreshing in a sterile action-film landscape, and there are a couple of expertly executed set pieces, such as an armored raid by Chon and Ben on a rival’s camp, that prove the director remains in control of his prodigious technical gifts. This is a grand-looking movie, and the editing is precise. Stone takes moments many other directors might ignore — such as a potential speeding ticket that threatens to erupt into violence — and expands them into big, memorable beats.

But to what end? The superb craftsmanship and care behind “Savages” only helps to underscore what an asinine, unconvincing picture this is.

“Savages” is filled with a variety of insulting elements: Del Toro’s pathetic Mexican accent; the incessant voiceover narration by Lively; the premise that a woman such as Elena could maintain control of a volatile crew of killers. What pushes “Savages” from mediocre into outright awful is the movie’s ending, a bait-and-switch cop-out of such enormous proportions, it becomes the biggest shock in the movie. After rubbing your face in garish excess, the film punks out. “Savages” talks the talk but doesn’t walk the walk: For the first time in his career, Stone comes off as a poseur.

"Savages" is rated R and is showing at UEC Theater 12.