Even with a pop music-obsessed 7-year-old in the house I'd managed to resist, or block out, the charm of One Direction. Presented on the big screen in loud, slick 3D they're a little harder to ignore and, to my surprise, even harder to dislike.
I now know what every teenage girl in the world is already across. Liam, Louis, Harry, Zayn and Niall are lovely working-class lads who tried out unsuccessfully as individual singers on Britain's 2010 X- Factor, but were then asked to continue in the competition as a boy band by judge and producer Simon Cowell. They've gone on to make music history by being No1 in 37 countries and are nothing short of a phenomenon - it's a remarkable story for a boy band who can't really dance.
For a man who mostly likes to make films about himself, either eating McDonald's (Super Size Me) or trying to fund a movie through advertising (The Greatest Movie Ever Sold), director Morgan Spurlock keeps out of shot. A more conventional documentary, this is a behind-the-scenes tour loaded with plenty of concert footage, interviews and screaming fans.
He's managed a few Spurlock quirks, though. A neurologist is included in a comical piece explaining how the brain works and why One Direction fans aren't "crazy", just "excited", and there's use of eye-popping graphics over live concert footage, which makes the numerous musical performances more interesting.
Mostly though, it's a backstage look at the gruelling schedule of a world tour, while also showing the boys being idiots and following them home for a little soul searching.
Interview snippets are spread throughout, with the boys talking about how the band works, dealing with fame and fans, and pondering what they'd be doing if they hadn't auditioned for X-Factor.
Insightful? Not really. Genuine? Occasionally.
When any of the band talk about the downside of constant touring and their unusual lives they very quickly adopt an appreciative tone - you get the feeling it's been drummed into them that they have a one in a million opportunity.
Spurlock cements the One Direction brand: selling cute, fun, harmless boys who just want to have fun and sing about making out. There's no sign of sex, drugs or rock'n'roll, but it's hard not to get caught up in the band's infectious enthusiasm for life and drive to make hay while the sun shines.
Other than the collateral damage of parents getting to know enough to have a favourite - Liam, if you must know, he's simple and sweet - Spurlock is preaching to the converted. This documentary is for the fans. They deserve it, as Simon Cowell says at the beginning of the film; teenage girls on social media are responsible for the One Direction worldwide phenomenon. At least we know who to blame.
Cast: Liam Payne, Harry Styles, Zayn Malik, Louis Tomlinson, Niall Horan
Director: Morgan Spurlock
Running Time: 92 mins
Rating: PG (Coarse language)
Verdict: A light, fluffy and ever-so-cute promotional piece.