When the film begins, we learn that the cheery little critters used to be a delicacy for the Bergen, a miserable race who got their fixes of happiness by eating Trolls, especially during their annual Troll-stice festival. But for the last two decades, the Trolls have lived in harmony after a daring escape from their home in Bergen Town. Princess Poppy (voiced by Anna Kendrick) is irrepressibly happy all of the time, while grey-faced Branch (Justin Timberlake) doesn’t have time for singing and hugging while he’s fortifying his home against the expected return of the Bergen. This one has gone through a number of iterations and it occasionally shows in the final cut. Originally planned for a 2015 release, starring Chloë Grace Moretz and Jason Schwartzmann, DreamWorks remounted the whole thing when they acquired the exclusive worldwide licence for the troll toys from Dam in 2013, and made it into a springboard for a highly merchandisable franchise. Unfortunately, it bears the wear and tear of a massive licence riding upon it. Changes during production are always more obvious in animated features because it’s trickier to edit and you can’t reshoot it. If there’s one thing trolls know, it’s bridges, and narration and Poppy’s love of scrapbooking arcs over a couple of the bumpier bits, but it feels like a sub-plot or two might have fallen out of the movie in the process. Looking at how they started out with Shrek, this feels like the studio has come full circle, skewing closer to the Disney musical than in anything else they have made to date. Their films usually make hefty allowances for music clearance in the budget, but Trolls has characters burst into song as a matter of course, which makes it their first ever run at a bonafide musical. They’re frustratingly close to pulling it off too. Timberlake is billed as an executive producer for his contribution to the soundtrack, which includes five original songs, all of which are brilliant in the film. Timberlake’s Can’t Stop The Feeling was released as a single back in May and has already charted, but the film offers a couple of unheard gems too, like Get Back Up Again. But then there are the jukebox musical trappings, which feel like a reversion to the studio’s old tricks, even though the soundtrack is well curated all around by Timberlake. Covers of Earth Wind & Fire, Lionel Richie and Simon and Garfunkel raise a smile and there’s a really evocative modern remix of In The Hall Of The Mountain King that serves as a chant for the Bergens, but otherwise, it feels like the film could have benefited from a wholly original soundtrack. If you have kids, you can expect to hear some of these songs over and over again in the coming weeks, but it won’t hold a candle to Frozen in terms of playability. The studio’s tenacity for celebrity voice casting continues unabated and in addition to Timberlake, Kendrick and Baranski, the cast list includes the singing pipes of James Corden, Zooey Deschanel and Icona Pop. Another shortcoming in the soundtrack is that Baranski, a Broadway icon, doesn’t get a chance to sing a typical villain song, original or otherwise, although the very fact that they’ve cast her makes it feel like they might have intended to at one point during production. Trolls is cheerier and more colourful than just about any animated film this year and it offers a couple of good laughs too. However, even if this is intended to kick-start a franchise, it never quite rises above its merchandising goals. There are musical highlights, but it plays more like George Lucas’ little-seen animated fantasy Strange Magic than George Miller’s Happy Feet films. In the year that Disney’s Zootropolis outdid DreamWorks at their own game, the corresponding attempt at Disney’s style is charming if not especially memorable. Trolls is in UK cinemas from October 21st. Follow our Twitter feed for faster news and bad jokes right here. And be our Facebook chum here.