Directed by Dax Shepard. Starring Dax Shepard, Kristen Bell, Bradley Cooper, Tom Arnold, Joy Bryant 15A cert, general release, 99 min

OH, LOOK. IT’S one of those genres they just don’t bother with any more. In the 1970s, you could barely move for films concerning wise-cracking rebels driving dangerously across the US. Unless the movies were lying to us (as if), to cross the road in rural Utah was to risk serious injury by vehicles stuffed to the windshield with the likes of Goldie Hawn, Burt Reynolds and Susan George.

Dax Shepard, a familiar supporting player, has attempted to revisit that world in a film that, though strong on broad comic turns, never quite makes sense of its core relationship. Shepard, also director and writer, plays a slacker living in mysterious comfort near a small hot town. When his girlfriend (played by Dax’s real-life squeeze Kristen Bell) decides to accept a teaching job in Los Angeles, he offers to drive her there.

But we have a problem. It emerges that Shepard was in a witness protection scheme and the couple soon find themselves pursued by the law, Bell’s ex-boyfriend and various comic hoodlums. Cue vast numbers of saloon cars crashing energetically through police roadblocks.

Well, not really. There is a lot of boring Clarksonian chatter about motorcars, but, inhibited by a modest budget, the stunts prove to be depressingly unspectacular. When stuck for something to do, Dax drives his car round

in tight circles – I believe “donutting” is the phrase – suggesting an automotive dog trying to scratch its wormy bottom. Meanwhile, he and Bell squabble with such conviction that one ceases to believe they could ever have contemplated a life together.

The film is not without its laughs. Bradley Cooper (dreadlocked and nasty) and Tom Arnold (gay and stupid) manage to make something of their bold cameos. But Hit Run never gets past third gear. It quickly runs out of gas. It blows a tire before escaping the starting grid. It . . . Oh, you can finish this review yourself.