I remember when I saw the first teaser trailer to Epic almost a year ago. Set to the gorgeous strains of Snow Patrol’s What If This Storm Ends? It looking genuinely stunning. Armies of tiny people dukeing it out in the grand green undergrowth of a regular family garden. It was Avatar meets the Flower Fairies, with a healthy dose of Mayazaki Hayao thrown in for good measure.

The final version of Epic does indeed feature all of those elements (except for the Snow Patrol), but is offset by a Wizard of Oz-like narrative that sees plucky teen MK (Amanda Seyfried) miniaturised in the woods outside her father’s remotely located house. There she encounters a dying princess who entrusts her with a mission upon which hangs the fate of the entire forest.

MK is accompanied by a world weary guardsman, a young anti-authoritarian hero type, a comedic slug/snail duo and off they go to see the Wizard, or save the forest, or do whatever it is they need to do before Christoph Waltz’s sinister rat/bat creature makes everything wilt and die. Why? Coz he’s evil.

Back in the human world, the film flirts with a couple of fairly adult themes. MK has recently lost her mother, is estranged to her father, who is far more preoccupied with tracking down the miniature civilisation he is convinced exists at the bottom of the garden than with consoling his daughter or managing his own grief. Unfortunately, the film is somewhat reluctant to deal with these dark clouds in any specific or potentially informative way.

Epic looks fine. Not great, certainly not epic, but pretty decent, and does its best to make use of the 3D depth of field. Director Chris Wedge has the original Ice Age and the disappointing Robots on his CV, but there’s a good natured tone to Epic that makes it difficult to truly dislike.

That said, the slimy comedians (Chris O’Dowd and Aziz Ansari) feel totally out of place, and a number of the voices – Colin Farrell’s leaf man in particular – don’t come close to matching their onscreen persona. However, we do get Steve “Aerosmith” Tyler as a wizened caterpillar, so it’s not all bad.

Ultimately, Epic feels somewhat perfunctory and after-the-fact, bringing nothing to an increasingly spectacular and envelope-pushing age of animated entertainment. It’s probably too earnest for teenagers, but should keep younger viewers quiet for a couple of hours, although they would benefit far more from exploring the magical worlds of Studio Ghibli.