Blame it on the law of diminishing returns: as his filmography grows ever larger, and his characters grow ever more violent, Oliver Stone seems increasingly less likely to engage audiences.

So it goes with “Savages,” the story of three young Californians — all blessed with beautiful faces and the bodies to match — who revel in a hedonistic lifestyle and profit from the booming marijuana business operated by two of them. Botanist Ben (Aaron Johnson) is a Berkeley grad with a knack for growing high-grade pot and a heart for high-minded charitable causes, while his friend Chon (Taylor Kitsch), a former Navy SEAL in Iraq, has a nose for  operations. The two, living the life in ever-sunny Laguna Beach, share enormous drug-trade profits, and enjoy the friendship and benefits of the same girlfriend, free-spirited blonde O (Blake Lively). All’s great until they stir up the anger of Mexican cartel headed by beautiful but vicious Elena (Salma Hayek), with the assistance of a cruel, leering right-hand thug played to the frightening hilt by Benicio del Toro.

Stone, working from a script he co-wrote with Shane Salerno (“Alien vs. Predator”) and novelist Don Winslow, seems to believe that the story’s contrast between a sunshiny SoCal planet and the darker world (no pun intended) across the border is provocation enough. It isn’t, particularly when it’s so tough to care much about what happens to the nominal lead characters. Far more interesting are Hayek’s crime boss, and her own emotional vulnerabilities, and a wisecracking but clearly doomed DEA guy played by John Travolta with loads of freewheeling comic zest. I wanna know more about those characters’ back stories and future adventures, not those of the beautiful, self-entitled rich beach kids. Minus points for the wimpy fake-out ending.