What do the Avengers, The Dark Knight Rises and Man of Steel all have in common. They fall down in the third act. They all start off pretty well, but all three fall apart at the end. When they expand into bloated action set pieces and the story is lost in an attempt to cram as much spectacle as possible, these films fail to capitalise on their promising opening and middle sections. Contrast these films to the great action movies on the 1980s: Aliens, Predator, Die Hard. These undisputed classics of their genre only become tighter and more focused in the third act. The action boils down to one-on-one conflict of hero against villain where good can ultimately triumph over evil.

Sure, there is plenty of spectacle in Aliens's final conflict but it does not end with a hundred eggs hatching and Ripley fighting off hordes of aliens. Instead it ends with her fighting the queen; it’s a battle of alien terror against a human fighting for survival.

In the end these films become a distilled version of themselves, not an expanded version filled with nameless, faceless, pointless characters who only exist to be punched by the heroes. Many Hollywood action blockbuster now have a third act problem; however good they are in their set-up and development, these films fall apart at the resolution stage.

So does the latest offering from Marvel, Thor: Dark World break the mould?

The quick answer is that this film is much better structured than previous Marvel titles. The plot flows together well and leads to an appropriate conclusion. After the film-makers have established the main characters in the audience’s mind they can get on with the action, skipping the need for a tedious ‘introducing everyone’ stage.

The plot of Thor: Dark World is little more than an excuse for a series of action set pieces. It makes little sense and hangs on a series of bizarre coincidences. At some time in the distant past Thor’s grandfather defeated a race of dark elves who wanted to destroy all light using a weapon known as the Aether. Now the nine worlds are about to align and the dark elves have returned to use the Aether to destroy them all.

Thor’s love interest Jane Foster (Natalie Portman) accidentally finds the Aether in an abandoned warehouse in London, which is pretty convenient given otherwise there would no point in having her in the film. Thor (Chris Hemsworth) returns to save her from the dark elves, have a brief period of emotional angst and then stop the dark elves destroying all nine worlds. The only snag is that to do all of this, he must enlist the help of his treacherous brother Loki (Tom Hiddleston).

It’s not uncommon for action blockbuster to place the plot and characters as secondary to the action, and in this case it is worth the series of beautifully designed, thrilling set pieces. It is also nice to see that this movie does not end with excessive property damage like Man of Steel & Avengers. That was getting boring. The final action scene in Greenwich doesn’t lack spectacle but manages to keep the action much tighter in focus as Thor battles against the dark elves’ leader (Christopher Eccleston).

Ending the film with Thor facing off against a super-villain is much more interesting than watching a group of people fight an army of faceless alien villains whose motivation is unclear at best. I can see why it was necessary to end the Avengers that way; watching six superheroes fight one villain wouldn’t be that thrilling. That’d be a pretty one-sided fight as the Avengers are pretty bad-ass.

However in creating these characters who possess enormous power, I feel the film-makers have lost the relatability of their protagonists. Die Hard’s John McClane is an everyday man in a strange situation, something we can all relate to. Superheroes are special by their very nature and are thus more difficult to relate to. Thor makes this problem worse by asking the audience to place themselves in the shoes of a Norse God.

We are supposed to relate to Thor via his real world problems – namely, his love life. Thor’s father Odin (Anthony Hopkins) wants him to find a nice Asgardian women like Sif (Jaimie Alexander) who has no discernible personality and almost no screen time. However, there is no tension in this story, partly because of Alexander’s lack of screen time and partly because it is clear from the start that Thor and Jane Foster will end up together.

The rest of the film has little emotional resonance. The big emotional moment in the middle of the film falls flat and doesn’t make Thor any more sympathetic as a character. This isn’t helped by Hemsworth’s terrible, wooden performance.

The rest of the cast are little better, however. Eccleston is unrecognisable under layers of make-up and does little more than fill the role of a two-dimensional villain. Hopkins phones in his performance and the usually very watchable Portman is on worse form than usual.

Idris Elba, who could act the socks off the rest of them in this sleep, turns up for five minutes as a pointless character. Only Hiddleston as Loki delivers in the movie. He is the only one with a credible emotional reaction to the main emotional scene. Hiddleston clearly delights in playing the trickster Loki and manages to be both funny and dark alternatively throughout the film. All the other characters are either there as window dressing or are completely pointless.

Thor is still a great character for an action movie: tough, courageous, lots of enemies to fight and nine worlds to save. The series of action set pieces both in London and in Asgard are breathtaking and stand up to the impressive legacy of action scenes the Avengers movies have built up. The visual effects, set design and combat choreography are all excellent which is what you want from an action film.

Despite this I was left with the feeling this was a very average movie. In many ways, it was acceptable and somewhat of an improvement on previous films in the franchise, but it offered nothing new or innovative.

I preferred the more paired down ending to a huge expansive set piece, the characters came through better and none of the visual impact was lost. Overall Thor: Dark World is one for the Avengers fans. They’ll love it for sure, but the general cinema audience might be left a bit cold.