Savages, Oliver Stone, 140 mins (15) Now is Good, Ol Parkerm 103 mins (12A) Untouchable, Eric Toledano and Olivier Nakache, 112 mins (15)

Stone gets high on his own supply

Oliver Stone's new film, Savages, sounds as if it should be a guilty pleasure. Its pretty young heroine, Blake Lively, and her two lovers, Aaron Johnson-Taylor and Taylor Kitsch, live in a beachfront menage à trois in Southern California. They fund their blissful existence by growing the world's best cannabis, a multimillion-dollar enterprise that attracts the attention of Salma Hayek's Mexican cartel. When Johnson and Kitsch refuse to do business with Hayek, she negotiates by kidnapping Lively and promising to decapitate her if her boyfriends don't sign on the dotted line. Kitsch, an Iraq war veteran, favours a guns-blazing response, and Johnson, supposedly a peace-loving hippie, soon comes round to his way of thinking.

Spending time with such a detestable bunch was never likely to be very edifying, but Savages could, at least, have been a good, old-fashioned orgy of sex, drugs and mindless violence. Unfortunately, it seems that Stone was smoking too much of his characters' own product, because his bloated film drags on and on without a scintilla of urgency. While we wait for the action to get started, we have to sit through endless, waffling conversations, and far too many inconsequential scenes featuring the most minor of supporting characters. I can only assume that every member of the cast had a contract guaranteeing them a certain amount of screen time, because why else would Stone make us watch Lively wandering around a shopping mall for what feels like hours?

To be fair, Hayek brings some depth to her character, a strong but lonely single mother who just happens to dabble in homicide, and Benicio Del Toro savours the nastiness of his role as her diabolical henchman. But Kitsch and Johnson don't have one leading man's-worth of charisma between them, and Lively – by name if not by nature – loses us in the film's opening minutes with her awful stoner narration. Johnson is "spirit" while Kitsch is "earth", she tells us. Johnson is a Buddhist, but Kitsch is a "baddist". Every grating word she says is an argument against the legalisation of cannabis.

You might not think that a dying teenage girl could be as obnoxious as the tripper-happy drug pedlars in Savages, but Dakota Fanning manages it in Now is Good, adapted from the teen-lit hit Before I Die. Adopting a not-quite-English accent, and suffering from one of those rare strains of terminal cancer which don't make you look ill, Fanning has a petty list of experiences she wants to tick off before her death (including shoplifting and becoming famous), but most of this bland, Brighton-set comedy-drama concerns her banal romance with the hunk next door (Jeremy Irvine).

A hymn to adolescent self-absorption, Now is Good may go down well at 14-year-old girls' sleepover parties, but my sympathies were with Fanning's divorced parents (the excellent Paddy Considine and Olivia Williams), not just because their daughter is about to die, but because she's such a stroppy, narcissistic know-it-all in the meantime.

Untouchable is based on the true story of the friendship between a wealthy quadriplegic Parisian (François Cluzet) and the Senegalese ex-con (Omar Sy) he hires as his carer. It was a huge hit in France, but it's fundamentally a conventional, soft-centred odd-couple comedy: Cluzet teaches Sy about modern art and poetry, while Sy introduces Cluzet to marjuana, call girls and such cutting-edge contemporary music as Kool & The Gang. The film's only surprises are its lack of conflict, and its refusal to make any political points about the two men's vastly different backgrounds. Still, it's slick and engaging, with a brace of lovable performances. This week, that's the best you'll get.