Part concert movie, part bio-sketch and all commercial, “One Direction: This Is Us” is yet another slam-dunk for Simon Cowell’s flavor-of-the-month boy band, whose myriad fans will eat it up as fast as they do the guys’ songs and high-priced arena tickets. It doesn’t hurt that its subjects—Niall Horan, Zack Malik, Liam Payne, Harry Styles and Louis Tomlinson—come across as the sort of very pleasant chaps tween girls’ mothers wouldn’t hesitate to invite over for dinner and gush over afterwards, or that the picture is expertly directed, handsomely shot, spiffily edited and—perhaps most important of all—well recorded. Of course self-styled musical sophisticates will scoff at the quintet’s bubble-gummy sound, the fact that they don’t write their own songs, and their failure (with one exception) to play instruments in their act. But success in the form of hordes of screaming, devoted fans is hard to argue with.

The saga of One Direction’s creation is well-known, of course. The five were originally solo competitors on Cowell’s British version of “The X-Factor” in 2010 but failed to advance. Cowell then had a brainstorm and put them together as a group, and in that form they came in third on the program. Though they didn’t win, through social media and tours their popularity exploded and their first album became a smash. An unkind but apt comparison might be drawn to the Monkees, the group created for an NBC TV series in 1966. Because of their obvious mimicry of the Beatles, they were often dismissed as the Pre-Fab Four. One Direction might be called the Pre-Fab Five, since like the Monkees they didn’t join one another naturally but were pretty much constructed from scratch by Cowell.

Now, three years later they’re an international phenomenon, as Morgan Spurlock’s movie—on which Cowell served as producer—clearly demonstrates. The concert footage of the English/Irish group, much of it shot at their appearance at London’s 02 Arena but with excerpts from performances at various venues during their worldwide 2012-13 tour, shows rabid crowds, members of which express their undying love directly into the camera. Interspersed are sequences in which the boys cavort about backstage (often to the distress of their anxious security detail), sightsee around the locales they visit in touristy fashion (though they’re swamped by fans when recognized), and offer observations about their unexpected success and how they feel about it. Spurlock also follows them on their increasingly rare trips back home to visit with family and friends.

What comes across loud and clear isn’t just that while the music they make may not represent the pinnacle of art, it’s catchy and easy on the ear. And the footage is calculated to emphasize that though they’ve hit it big, these are still normal lads at heart, no swelled heads among them, solicitous of their families (one is shown nearly breaking down when his mum thanks him for buying her a house, while another is best man at his brother’s wedding), still at ease with their old friends (another visits the bakery where he used to work and hugs his old boss, a chipper old lady) and genuinely chummy with each other on the long trips to the next concert. Again and again they thanks their fans—who, we’re told repeatedly, were the real key to their unlikely success, embracing them when they were runners-up in a television contest and spreading the word via tweets and e-mails. And they’re aware that the adoration they’re getting might not last and they might go the way of so many barely-remembered bands before them, and they seem okay with that, choosing to ride the wave as long as it lasts.

Of course, it’s hard to know how much of this is spontaneous and how much carefully staged. Certainly some of the boys’ off-stage antics have a lot of “A Hard Day’s Night” and “Help!” vibe to them, while a camping trip during which they reflect on the roller-coaster they’re on has a calculated air. Sequences in which some of them disguise themselves to interact directly with their fans are obviously planned well in advance. And in terms of their normalcy, it has to be remembered that it’s still early days and there’s plenty of time for darker aspects of their personalities to emerge, depending on how long their longevity is—a very uncertain thing in the boy-band world.

But at this moment in time, there’s nothing wrong in their enjoying their celebrity, however long it lasts, and it’s certainly understandable that Cowell should take the opportunity to add to the piles of cash they’re bringing in with a film like this. It’s a first-class job from the production standpoint, with Spurlock—not the most obvious of choices for the task—and his talented crew capturing the performance material in visually exuberant style (with the 3D used pretty effectively) and the off-stage footage capturing, or mimicking, a suitably fly-on-the-wall air. And it manages to differentiate the five guys nicely, with Styles coming across as the most self-consciously “on,” Malik as the most quiet and introspective, and the others falling in between the two. The result is more no-warts-at-all than warts-and-all, to be sure, but the boys’ “Teen-Beat”-buying fans would hardly want a “Behind the Music”-style expose anyway.

As one watches “This Is Us,” though, it’s possible to feel an urge to advise the guys to invest their earnings wisely. If musical history is any guide, the well won’t be a gusher forever.