The trouble with prequels is that the future is already mapped out, unless it’s Star Trek 2009, in which case the future has just been radically changed by a Romulan rebel. There are no handy Romulans in the X Men universe, so with X Men First Class, the attraction is not wondering what will happen, but how it happened – How Magneto went to the Dark Side, and how Professor X ended up in a wheelchair – and who they were to start with.

Set in the 60s, with a new generation of baby boomer mutants just getting jiggy with their powers, and the cold war heating up, X Men First Class posits a ‘secret history’ of the Cuban Missile Crisis in which the mutants, naturally, played a major role. As a baby boomer, and a profoundly dedicated JFK supporter, I’m not sure about this historical hi-jacking at all. It was Kennedy’s courage – and ours, in supporting him and quietly accepting that this might be our last day alive – that got us through.

But the real question is, is this movie worth annoying grumpy old baby boomers like me? Sadly, no. It is full of holes, some very poor acting, and just looks awful. Considering this came from the same stable of comics and movie making as Kenneth Branagh’s awesome Thor, it fails on almost every level. The casting in Thor was impeccable – the casting here looks like it was done in the dark, and Matthew Vaughn’s direction amounts to “read this – walk over there.”

First of all, there is no way that James McAvoy is a younger Patrick Stewart. Everything is missing here, and not just the bald head. Stewart packs decades of expertise, charm and talent into the role. McAvoy brings nothing to the table, but if he is bad, Michael Fassbender fares worse, having to follow the wonderful Ian McKellan. The two of them simply lack the chemistry and charisma of their older counterparts and maybe they sum up what is wrong with acting today compared to Stewart and McKellan’s generation.

The rest are kind of forgettable – beside Rebecca Rominj, Jennifer Lawrence is just wet, and casting January Jones as Emma Frost was clearly just meant to cash in on her blondeness and Mad Men popularity. Do like the way she cuts glass with her fingernails though. In fact, the only member of the cast who looks like he should be there is Kevin Bacon as Sebastian Shaw – but then what else would you expect? Nice to see him again.

There are laughs – like the young mutants using their powers to trash a CIA waiting room – but some of them are unfortunately unintentional, such as the nuclear warheads going back and forth like a pantomime gag – “here they come! No, there they go – no, here they come again!”

All in all, after all the hype, a big let down. But they can’t all be Thor.