Ham-and-pineapple express: "30 Minutes or Less"

30 Minutes or Less, director Ruben Fleischer's follow-up to Zombieland, operates under two different impulses. Part of it is a delayed coming-of-age picture in which lowly pizza delivery boy Nick (Jesse Eisenberg) struggles to hang on to the relationships that matter to him: with the girl he loves (Dilshad Vadsaria), who's leaving their hometown of Grand Rapids, Michigan to start a hotel management course in Atlanta, and with his best friend Chet (Aziz Ansari), who himself has started climbing the career ladder, away from minimum-wage minions like Nick. Increasingly, all these latter two have in common are the action movies they rent and watch together, and their friendship will be unexpectedly sustained when they find themselves bang in the middle of an action-movie scenario: think Danny Glover straining over a toilet full of explosives.

While making a delivery one night, Nick is kidnapped by a pair of local drongos (Danny McBride and Nick Swardson) who strap a bomb to our hero's chest and encourage him, in the strongest possible terms, to rob a bank for them. At which point, the film's more commercial instinct kicks in, and 30 Minutes or Less turns into a slacker action flick, necessitating the haphazard waving around of guns, much pedal-to-the-metal business (usually interrupted by stop-offs at certain fast-food outlets), and not uninspired use of Glenn Frey's Beverly Hills Cop anthem "The Heat is On". As the less Caucasian half of the central duo, Ansari even gets his own, Glover-esque catchphrase: "I just want this goddamn day to be over."

The precedent here is David Gordon Green's Pineapple Express, which blew in on a cloud of dope smoke and, though very funny in places, favoured the big and the loud, partly just to register with its chosen stoner demographic, partly to distinguish from the quietist aesthetic of the director's previous work. Fleischer, rightly not feeling himself ready for a Jerry Bruckheimer budget just yet, keeps 30 Minutes small-seeming and manageable - the key is the Datsun the leads steal as their getaway car - inviting his performers to maintain the improvisatory looseness of the post-Apatovian comedy universe from which they've been drawn. Eisenberg and Ansari do a workable re-run of bromance dynamics familiar from TV's Psych and Scrubs, there are nice riffs - frantically Googling for defusal tips, Chet despairs "there's no consensus in the bomb-making community" - and nice scenes: Grand Rapids turns out to be ironically named, a town so small that two money drops might be arranged for the same place at the same time, only prolonging the chaos.

Still, as becomes increasingly clear, nobody here is really cut out for action movie business, which is both the joke, and a limitation of the film going into its second and third acts. Not even the livewire Ansari, the very definition of a high-energy performer, can match the blazing sharpness of Eddie Murphy at his peak; the villains, meanwhile, are manchildren with daddy issues - introduced watching Friday the 13th Part 3-D, most commonly heard discussing blowjobs - so there's little real sense of threat, or indeed of the clock ticking. (Though the rowdy McBride, an acquired comic taste whose preferred way of exiting any given scene is suddenly announcing "I gotta take a shit, dude", is becoming more adept at selling his stock-in-trade bluntness.)

Fleischer has a certain fun getting these characters into their John McClane-ish pickle, but not much of an idea of what to do with them once they're there, save to pay off an earlier "That's what she said" set-up, and cobble together a few reshoots in lieu of a properly satisfying conclusion: the fate of one character, last seen bleeding out, is completely forgotten in the rush to get to the wrap party. In the end, it's probably not a case of too much action, not enough comedy (which was the Green film's biggest flaw), but too much slacker, not enough action-comedy - a reminder, albeit a halfway enjoyable one, of the sheer hard work and commitment required to make these scenes and tropes truly fly.

30 Minutes or Less opens nationwide tomorrow.