Some movies are critic proof. It doesn't matter what any reviewer says about the plot/acting/directing style of a Twilight, Harry Potter or Miley Cyrus movie, dedicated fans are going to line up around the block and the film will find itself at the top of the box-office charts on its opening weekend.

Like the aforementioned titles, Justin Bieber's new documentary, 'Never Say Never', would seem to be another that falls under the heading; "it really doesn't matter what you think as a reviewer, the kids are having a great time, so get back in your box, grandad."

But here's the thing.

While undoubtedly aimed at the star's legion of die-hard tweenage girl fans, 'Justin Bieber: Never Say Never' is a well-made documentary that also serves as a sociological study into the power of social networking and the cult of personality.

For those non tweenage girls, a quick recap. Justin Bieber is a 16-year-old, God-fearing chap with a distinctive haircut and a pleasant voice who grew up poor in Ontario and dreamed of making it big in the music business. Within a few months of posting videos singing his favourite songs on YouTube, Bieber mania was growing and the hit count on these rough clips thrust the teenager into the online popularity bracket traditionally occupied by keyboard-playing cats and sneezing pandas.

'Never Say Never' chronicles the global rise of Bieber mania from YouTube wannabe to an artist who can sell-out Madison Square Garden in 22 minutes. Director Jon M Chu employs a combination of home movie and concert footage that shows the Bieber boy as a well-rounded, hard-working young man who doesn't seem to have let the trappings of fame rob him of his childhood.

Teen idols come in many shapes and forms, from Donny Osmond and David Cassidy (both of whose popularity puts Bieber fever in the shade, by the way), to current idols such as Miley Cyrus and Jedward, the first of whom shares the stage with Bieber for his Madison Square Garden moment. Bieber's rise has been more meteoric than any of them (within what seemed like a month, my goddaughter had removed all her Zac Efron and Hannah Montana posters from the bedroom wall and replaced them with this fringed wonder) but it's still unclear quite how his career will play out when his audiences grow slightly older and become more discerning.

For the moment, the signs are good. Young Justin is giving his concert audiences exactly what they want. And judging from the decibel level of youngsters at the Irish premiere of his new documentary, he's giving cinema audiences exactly what they want, too.

There are certainly quibbles. It would have been interesting to learn more about his difficult upbringing; being raised by a single mom on a small salary, etc. The whole 3D thing is a bit of a swiz, too. Most of the film is in 2D, apart from the concert footage, during which young Bieber points out towards the audience a grand total of five times, scarcely enough to warrant having to wear the clunky specs for 105 minutes.

For the core audience of this film, however, these quibbles are minor. Teenage girls are going to lap it up; teenage boys are going to be under pressure to get their feathered haircuts in order, and Bieber moms are going to have to get used to growing demands for photos, CDs and concert tickets of their idol.

At least until the Next Big Thing rolls along.

Michael Doherty