The inherent problem with the Marvel Cinematic Universe is that it's constantly under threat of imploding under its own weight. The bigger it gets, the more complicated things become - and it is getting bigger. Look at it like a Jenga tower: it must be treated carefully, and with every addition that is made, you have to consider how it will affect the balance - and the overall harmony - of everything else that it's connected to. That balance needs to be keep in check at every turn, otherwise... well, we've all been at the end of a failed Jenga game. It's not a pretty sight. But how do you prevent something so big from toppling over once it has reached the huge climax it was so very obviously building towards over the sum of five years? Once that climax has been met, where else is there to go? These are the kinds of questions that the movies in Marvel's second phase are having to deal with in the wake of The Avengers, and one that Thor: The Dark World - as was the case with the recent Iron Man 3 - seems afraid to tackle head on. Then again, you can't exactly blame these movies for avoiding direct eye contact: the load is a hefty one. Iron Man 3, the first movie to follow Joss Whedon's fan-pleasing bonanza The Avengers, knew that it couldn't top the explosive power and sheer cinematic joy brought on through the teaming-up of our favourite Marvel heroes. Instead, it opted to go down a different route as something of an espionage thriller, existential in places, but mostly good old-fashioned fun with a few large-scale action sequences thrown in to appease blockbuster junkies. Many thought that writer/director Shane Black (renowned for his scripts built around witty dialogue cues and extended scenes of buddy banter) took the comedy too far, but in retrospect he was probably right to keep things light. To try and pile on another story with the weight of The Avengers (which ended in the destruction of half of New York City, remember) would have been too much too soon. And Thor: The Dark World seems to think similarly, though the end result - accomplished as it is - is perhaps not quite as convincing. Our story begins with a short prologue set a long time ago, which introduces us to our villain of the week, Malekith (Christopher Eccleston), who seeks to control a mysterious and rather vague elemental force named "Aether," which on its own terms isn't any more or less interesting than any of the other MacGuffin-like artefacts that drive the plots of MCU movies. When Thor's grandfather thwarts Malekith, he orders that the Aether be buried deep in the ground where nobody will ever find it, and Malekith is put into a kind of suspended animation. He'll be back later, of course. Two years after the events of the original Thor, The Dark World picks up the story with our eponymous hero (Chris Hemsworth on great form as the muscular Asgardian once again) on realm-cleaning duty in a distant land, fighting alongside his trusty sidekicks and his even trustier hammer to restore peace to the universe, though he's still sad and lonely without his lost love, Jane Foster (Natalie Portman), who remains on Earth and is pining for him similarly. There's something of a love triangle thread hinted it with Thor's faithful friend Sif (Jaime Alexander), but it's quickly forgotten. Meanwhile, in Thor's home world of Asgard, Loki (Tom Hiddleston) is banished to the dungeons for eternity by his father Odin (Anthony Hopkins, hamming it up again to delightful results) for all that bad stuff he did over the course of The Avengers. Loki is, by far, the most interesting character within the Marvel Cinematic Universe, and the writers made an excellent call bringing him back to the centre of the story again, in a plot which also allows for the God of Mischief and his brother to spend a little time on the same side. Through sheer coincidence, Jane stumbles upon the Aether and - because she has nothing else to do - becomes host to its power. This awakens Malekith, who sets out to reclaim the almighty force so he can - you guessed it - bring darkness upon the universe. The rest of the plot, overwritten and dull to the point of a headache, isn't worth the time it takes to explain, but merely provides a way for Thor, Jane and their ragtag companions to interact with one another between several realms. Most of the action is separated between London (now the go-to city for being blown up by Hollywood) and "the Dark World" (made unnecessarily darker if you're tricked into seeing it in 3D), which allows for a nice contrast of locations for things to get exploded in without it feeling repetitive. What's surprising about this Thor follow-up, then, is that the results are mostly hilarious. Against the odds, The Dark World is about as funny a movie as Iron Man 3 was, and very rarely chooses to take itself as seriously as its broody title seems to suggest it might have. The second half of the flick consists of almost nothing but characters quipping and making self-aware comments about their situations, in fact (Kat Dennings, who plays Jane's intern Darcy, talks only in witty asides and is one of the best things about the flick). Amusing as this is, though (and there are some truly brilliant London-based gags that you won't forget anytime soon), this approach doesn't completely work. In amongst the jovial beats of the movie, London is being torn apart, portals are being ripped open, soldiers are dying... and it's hard to know how to feel about it all. Nobody in the movie seems to be taking it entirely seriously, so why should we? And though Marvel almost certainly set out to make a movie in this vein, the final product is so light and fluffy that it almost feels like we didn't even need to see it playing out. Truth is, Thor: The Dark World is happy to exist as something of a placeholder, tiding us over until the next entry in the MCU when another Avengers-sized plot can be rolled out and we can start moving towards a finale that binds several characters together all over again. There are very few repercussions inherent to this standalone story, and though the plot yearns to operate on a huge scale (and by the standard of a regular blockbuster, it does), it doesn't execute itself as such because it's afraid to break the mould or take risks. Still, as a placeholder - a middling MCU entry, if you will - it's a pretty good one. Though the plot threatens to bore the heck out of you at certain points during the opening half hour (and you'll still find yourself wondering why Natalie Portman is wasting her time with such a bland love interest character), soon enough the movie seems to realise how silly it all is and skyrockets head-first into a series of chases sequences and extensive battles. Once The Dark World gets going, it doesn't slow down, and though there isn't really a noticeable "direction" on show in narrative terms, there isn't really any filler either. Unfortunately, the movie is let-down somewhat by its villain, who remains a cardboard cutout from start to finish. There's nothing interesting or memorable about Malekith, nor is he particularly scary or intimidating to watch. He doesn't have a real motive, or notable traits. He's just "the bad guy" here, which is a shame, given how great most of the villains fuelling the movies in the MCU have been so far and how talented an actor Christopher Eccleston is. Thankfully, the Jenga tower still remains upright, and director Alan Taylor (known for his work on TV's Game of Thrones) can rest easy knowing that it he wasn't the director to send the bricks tumbling down (we're still waiting for that poor guy, whoever it may be). Then again, Taylor doesn't seem to have been given the opportunity to try. At first it might seem as though he was a natural choice to helm a Thor movie, given his associations with Medieval fantasy, but the real reason for his hiring becomes more apparent when you sit down to the movie, which has been directed with a complete lack of personality. It might as well been have been directed by a Marvel supercomputer operating a built-in algorithm or by producer Kevin Feige himself (there's a thought). That's not to do Taylor's work here any discredit - the film looks spectacular, the action scenes are thrilling and fun, and every aspect of production has been handled with a cool competence. To say you feel as though you're in safe hands from start to finish is perhaps the exact result that Marvel sought to achieve - sign a director with a proven track record who they could get to do the hard graft as they "guided" him through the process, ensuring that he never veered too far into any controversial territories. But whereas Iron Man 3 still felt like it had been helmed by Shane Black, then, and the original Thor had Kenneth Branagh's Shakespearean fingerprints all over it, Thor: The Dark World feels entirely like a product straight off of the conveyor belt. At this point in time, maybe that's what the MCU needs to keep things on the straight and narrow, but there's something almost creepy and inarguably factory-like about this installment that will perhaps make true cinephiles feel uncomfortable. Will Marvel fans love the hell of it anyway? By the hammer of Thor, yes. Still, for all the Gods and supernatural beings on show here, it's the human touch that's sorely lacking. Planning to see Thor: The Dark World? Let us know your thoughts in the comments section below.