We all knew it would work, didn’t we? Margot Robbie as Harley Quinn. Arguably, there’s never been a better match of actor and character in a superhero movie (except maybe Jack Nicholson as The Joker, but that was decades ago).

And with the addition of Will Smith – reuniting them after their pairing in con film Focus – you know the lion’s share of scenes will have gone to those two. Not that that’s a bad thing. But when watching David Ayer’s Suicide Squad I did wonder – more than once – what the rest of the cast were actually doing there, other than to make up the numbers.

It’s a bit like the X–Men films. You have so many characters that giving them all something interesting to do is a tall order. Although maybe that’s just an excuse and the filmmakers should really just try that bit harder. (After all, we’ve had a few great X–Men films in the past.)

But to backtrack, in case you’ve not seen the trailer or know anything about superhero films or have any idea what the Suicide Squad is, let’s recap.

‘They’re bad guys. The worst of the worst’, says Viola Davis’ shady Government official Amanda Waller. For it is she that pulls the strings of the squad, getting them to do her evil bidding. And she’s as cold as ice with it, sending them into situations where you wouldn’t want to risk your precious heroes like Batman and The Flash.

Essentially, they’re canaries down the coal mine and very much on the expendable side. Bad guys forced to do good. For example there’s a Hispanic gangster fire guy (Jay Hernandez), a crocodile (Addiwale Akinnuoye-Agbaje), an Aussie boomerang-throwing burglar (Jai Courtney), a master assassin with funky dress sense (Will Smith) and everyone’s favourite deranged-by-the-Joker psychiatrist (Margot Robbie). Plus some other walking clichés but I’ve given up listing them, you’ll just have to check IMDb.

They’re tasked with rescuing someone from the remnants of a city that an ancient – and rather pissed off – witch called Enchantress (Cara Delivigne) has torn to shreds in a sort of Viggo the Carpathian from Ghostbusters kind of way. Plot wise, that’s kind of it. So somehow we have a film in which lots happens, but also, bafflingly, very little at all.

Furthermore, there’s been talk online of how the film starts about three times. Or that it takes maybe 20 minutes to get into the actual story. Either way, you could argue that – if you’re going to be tough to please like me – it never really does get going. Robbie does her best to lighten things up but it often feels like she’s in a different movie to everyone else.

Particularly Joel Kinnaman’s dour Colonel Rick Flag; who leads the group in such a gruff manner it’s as if he sucks the life out of scenes simply by turning up; like some sort of Dementor in army fatigues.

Then there’s the Joker. One of the best comic book villians ever to grace the screen and first made famous by Jack Nicolson, then updated for the modern age by the genius of Heath Ledger (the latter gaining a posthumous Oscar in the wake of his death).

So now we have Jared Leto giving us his take, going all method during the shoot; with stories of him sending dead rats to cast members there’s no doubt he got into character for the role. And really, this just added fuel to the fire getting us all revved up. His Joker would be something special. Even perhaps, whisper it, the best yet?

And then… what did we get? A couple of scenes here and there but largely diddly squat. Nada. Zip. Zilch. David Ayer took this great character and frittered him away on some meaningless encounters, giving Leto precious little to work with. But perhaps I am missing the point? Was this not a Joker movie? Is he not the biggest bad guy in the film? If not, then why bother to hype him up at all?

If you’re going to focus on Smith and Robbie’s characters then why not give them some sort of combined backstory and shared history the actors can sink their teeth into? Play up to their chemistry. Or if you’re going to do a Joker and Harley Quinn film, do that. With the rest of the squad as peripheral characters. Maybe Deadshot could have taken it upon himself to free Harley from the Joker’s influence?

I get that screenwriting is a monumentally challenging thing to get into any semblance of something coherent that’ll engage audiences. But surely if in doubt, KISS right? Keep it simple, stupid.

So structurally this film is somewhat all over the place and feels thrown together in a way which slightly vexes me. And it gives the audience very little with which to identify in terms of characters. Granted, ensemble movies are a tricky beast at the best of times and, whilst I’m loathe to use Marvel as a blueprint, they just do it so much better.

Whether bringing together established characters (Avengers) or introducing entirely new ones (Guardians of the Galaxy) they make it seem much more seamless and, crucially, make us care about the characters involved.

So, anywho. Before it seems like I’m too down on this whole movie, let’s put things in perspective. There were some good performances to be had (Robbie, Smith, Davis, Leto) and David Ayer did a passable job of setting up the squad and it’s a reasonable enough Friday night popcorn type of watch. So there’s that. And it also seems to have done well enough to suggest a sequel isn’t going to be a big ask of the studio.

So for the second one I really hope they come up with a better structure and more credible story for the squad. Stick Smith and Robbie front and centre and, for God’s sake, keep the tone as far away from dark and gritty as possible. DC has more than enough of that going around and superhero films are supposed to be fun. Aren’t they?