GNOMEO and Juliet, released in 2011, at least somewhat justified its existence as a Shakespearean tale transposed to the lively world of garden gnome-based shenanigans, with a genuine dose of wit and heart.

There’s no such luck with this innocuous but needlessly convoluted and thoroughly forgettable animated sequel – that seems to think a Christmas cracker-level title is enough to warrant a film.

Arthur Conan Doyle’s famous detective creation (voiced here by Johnny Depp) and his faithful sidekick Dr Watson (Chiwetel Ejiofor) get unceremoniously gnomified, hot on the trail of arch nemesis Moriarty (Jamie Demetriou), who for some reason wants to steal and smash all the garden gnomes in London.

Both Gnomeo (James McAvoy) and Juliet (Emily Blunt) cross paths and team up with Holmes and Watson when the rest of their gnome friends fall victim to Moriarty’s dastardly plan.

Sequels are always expected to aim bigger, but this is a prime example of how less was more. It expands things from the quaint confines of the garden to an adventure across London, meaning it lacks the charming small scale of the first film, just to jam together two entirely different animated films into one.

As a result, neither the world of the garden gnomes nor Holmes and Watson skulking about trying to figure out Moriarty’s next move feel fully realised in their own right. The plot feels at once flat and pointlessly complicated, to the point where you wonder if the young target audience might end up both bored and lost – a huge sin for this type of film.

The animation is very nicely done; particularly impressive is the little details on the gnomes themselves, such as the faint dirt patterns and the way the light bounces off the surface. But it’s a colourful mask for the stiffness of the jokes, a wasted all-star cast and the plodding blandness of the story.