‘If that boy were an apple, he’d be a Delicious!’ coos a smitten, female high school student as Zac Efron’s teen dreamboat struts through the hallways of 17 Again.

For the next hour-and-a-half, Burr Steers’s body-swap comedy bows down at the altar of the High School Musical pin-up as he single-handedly teaches the young people of the world how to behave with dignity.

Don’t have sex before marriage, don’t drink alcohol, don’t smoke, don’t throw parties when your parents are away, respect your elders, stand up to bullies, support your friends, dress like you’ve stepped out of a fashion catalogue.

Follow the gospel of Zac and you too can have girls swooning in your wake and guys clamouring to be your best buddy.

17 Again is glossy wish fulfilment writ large.

Thirty-seven year-old Mike O’Donnell (Matthew Perry) feels like he has been dealt successively bad hands by fate, with no end in sight to his misery.

His wife Scarlett (Leslie Mann) has thrown him out, his children Maggie (Michelle Trachtenberg) and Alex (Sterling Knight) despise him and, to add insult to injury, he has just been passed over for promotion at work.

In a freakish twist, Mike tumbles over a bridge into a whirlpool and is magically transformed into his 17-year-old self (Efron).

Having recovered from shock of the metamorphosis, Mike realises his new look is a gift not a curse.

‘This is my chance to have my life over, but to do it right.

I’m going back to high school!’ he tells sci-fi fixated best friend Ned (Thomas Lennon), who poses as his father to ensure he sails through the admissions process with Principal Masterson (Melora Hardin).

In his guise as the new boy, Mike bonds with his daughter and son, showing them the error of their hormone-driven ways (‘When you’re young, everything feels like the end of the world’) whilst reminding Scarlett that her marriage isn’t broken beyond repair.

17 Again opens with a gratuitous shot of Efron topless, dripping with sweat, practising his sharp shooting on the basketball court.

A superfluous dance number panders shamelessly to fans of High School Musical before the plot fast-forwards to the present day and a simple premise borrowed wholesale from It’s A Wonderful Life.

Efron carries the film with his natural charm, supported by a sporadically amusing Lennon as the elvish-literate geek who woos the Principal with his love of fantasy literature.

Potentially sticky moments, like teenage Mike being seduced by his daughter’s vampy classmates (‘I was kicked off the cheerleaders for being too flexible!’) never come to pass.

Screenwriter Jason Filardi keeps everything wholesome, inspiring the target teen audience to dream with his hero’s basketball mantra: ‘It’s not how big you are, it’s how big you play.’ 17 Again plays moderately well.

• Release Date: Friday 10 April 2009
• Certificate: 12A
• Runtime: 101mins

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