An overgrown kid in his forties whose maturation was arrested when his dreams of rock’n’roll stardom died, finds a new creative outlet playing music with a group of kids less than half his age. Not only that, but the opportunity to rock out again finally allows him to move on and grow up a little.

If the premise of The Rocker sounds familiar, that’s because, as I’m sure I won’t be the only film critic to point out, its similarities to the vastly superior School of Rock are glaringly obvious. Even the central character, the failed heavy-metal drummer Robert “Fish” Fishman, is played by a portly, hyperactive Jack Black-alike. Rainn Wilson is likely to be unknown to British audiences unless they have stumbled upon the American version of The Office or they have a memory for fleeting cameos in the film Juno.

We’re introduced to Fish as the gurning drum fiend in the poodle-haired rock band Vesuvius. The year is 1986 and Fish’s dreams of megastardom are about to be ground into dust by the ruthless mosh-pit of the music industry. The rest of the band trade their drummer for a record deal. Fish is left with his shattered dreams and a life in telesales to look forward to. All this changes more than 20 years later when Fish is asked to stand in as drummer in his nephew’s band ADD. After a shaky start, he rediscovers the power of rock.

The director Peter Cattaneo targets a younger audience here than he did with his most successful film, The Full Monty. The simple central story of friendship, loyalty and self-actualisation is cheerfully smeared with bodily fluids and gross-out gags, like a toddler playing with the contents of his nappy.

There are occasionally amusing moments, but the writing lacks the warmth that made School of Rock such a hit. But what really lets the film down is the music. It’s the kind of polished, pre-packaged angst-pop that makes the Jonas Brothers sound kick-ass. If the colour beige was a rock band, it would sound like this.

12A, 102 minutes

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