Fifth gear: "Fast Five"

Despite their multi-million dollar pricetags, previous instalments in the Fast and Furious franchise retained a pleasing B-movie vibe. Fast Five, the unofficial opening of 2011's sequel-heavy summer season, instead appears to take its inspiration from the bloated later series of its producer Neal H. Moritz's TV hit Prison Break, dispatching a crew of varyingly bulletheaded individuals armed with unexpected skillsets (wait, so Paul Walker now has the Ethan Hunt-ish ability to palm swipe cards and surf trains? Jordana Brewster speaks fluent Portuguese?) to an idea of Latin America that's been hot in every sense since the one-two of City of God and Amores Perros at the turn of the century. Everybody gets a free ride to Rio, and - as the current UK box-office chart suggests - even our kids and animators want a bit of that these days.

The new film faces, but never quite resolves, the franchise's usual problem of how to convince as badass within the limitations of a 12A certificate. This, after all, is a universe where the early, spectacular turning-over of a prison van momentarily containing Vin Diesel's Dom Toretto results in - on-screen news reporters helpfully reassure us - "miraculously, no fatalities"; where a whole squad of trained SWAT marksmen will fail to hit the fugitive Diesel (who is, let's face it, a big enough target) from a distance of approximately twenty yards; and where the cars have to be parked up for ninety minutes in the middle of the film, so the characters can hunch over maps and laptops in anticipation of a final-reel heist.

Muscles are flexed in Fast Five, but only rarely put to use; nevertheless, the whole film, growling and inflated to Michelin Man proportions, is very definitely on the 'roids. At times, it resembles nothing more than a stroke flick for nightclub bouncers. As the FBI agent charged with bringing Toretto and cohort Brian O'Connor (Paul Walker) back from their Brazilian vacation, Dwayne "The Rock" Johnson has renewed the gym membership that lapsed during his soft kiddie-pic period, and effectively turned himself into a walking Tom of Finland cartoon, complete with persistently comical facial hair.

The new film is interested in Rio as a location about as much as Fast Three (as we're probably now supposed to refer to it) was in Tokyo: i.e. principally to make itself more saleable in a particular market. The Latino characters in Fast Five are either crooks, jokes, crooks and jokes, or chicks in micro-bikinis: the franchise badly misses Michelle Rodriguez (from Fasts One and Four), and the veteran actor Joaquin de Almeida must, surely, be bored of having to play crime bosses called Señor Reyes (of course Señor Reyes!) who can think of nothing more original to do with their enemies than stringing 'em up in disused meat lockers. You go to Fast Five to watch American kids in American cars totally owning non-American turf. (As I first mooted around the time of 2003's 2 Fast 2 Furious - sorry, Fast Two - we may still be in Afghanistan merely to fuel the tanks of franchises such as these.)

So here they are then. In car one, there's Diesel, doing his very best to conceal the sad look of a performer who'd hoped he'd be doing more important work at this point in his career; in car two, Walker, whom you'd still struggle to pick out of a line-up, which may make him perfect for this sort of thing; and back at dispatch, there's Brewster, here debuting a lovely, shy smile, and apparently maturing into Julia Ormond. Whenever the film is roaring along behind the wheel, or elsewhere tagging along with these three - two brothers of a sort, and the sister one of them has got pregnant - Fast Five exerts a certain dopey charm: it's certainly an improvement on the third and fourth instalments (director Justin Lin has done all three, and is learning on the job about balancing action and character), if still a way short of regaining the freshness of the first two movies.

It just gets draggy whenever it moves away from the streets into garages, where barely remembered characters from the earlier films emerge from the shadows and are handed frankly unnecessary recalls: I wasn't much sold on Tyrese first time around (Fast Two), and his cause isn't helped by having to speak such trailer-ready lines as "This mission just went from mission impossible to mission-fricking-insanity." At such moments, Fast Five, or Fast and Furious Five, or whatever you want to call it, is fixed firmly with a large "L"-plate - not for learner, but lame, loser, lightweight. Still, I can offer you this, as both a recommendation and a warning: we will see far less entertaining sequels this summer. Stay tuned through the end credits for the surprisingly tasty set-up for (yes, you guessed it) Fast Six.

Fast Five opens nationwide today.