X-Men 2 (12A), *

X misses the spot

The time has come for those who are different to stand united. Their enemy: the ugly and the badly dressed. In X-Men 2, sequel to the $300m (£188m) grossing, Marvel comic strip inspired X-Men, a super-evolved, shape-changing female, aka Mystique (Rebecca Romijn-Stamos) lures a dumpy human into a toilet cubicle. Never one to shirk a dirty job, she tries to unzip his trousers, only to hear a gentle rip. "Velcro!" she sneers. "Nice!"

When not attending to fashion crimes, the genetically advanced concentrate on self-defence. This is because lots of people are out to get them. Meet General William Stryker (Brian Cox), whose hobbies include stroking his KFC beard and experimenting on mutants. His latest scheme involves drugging Mystique's imprisoned boss, iron-hungry Magneto (Ian McKellen), so that he'll spill the beans and allow Stryker to assemble a kind of mutant telephone network in his underground lair.

Have I lost you yet? X-Men 2 is a snobby creature, geared to fans who know X-Men backwards and are already dizzy with excitement about X-Men 3. But for those who missed the original, here's the gist. First time around, paranoid mankind wanted to get every gifted weirdo on to a register, while good guy Charles Xavier (Patrick Stewart) – who runs a school for mutants – battled to stop the humanphobic Magneto from wreaking revenge. Now, Charles and Magneto find themselves lumped together yet again. Stryker wants to identify the whereabouts of mutants and kill them all.

You can see the appeal of the X-Men: there's not an oppressed minority that need feel left out of this purge. One boy "comes out" to his mother and admits he's a mutant. The X-Men represent homosexuals! The White House is attacked by a mutant terrorist, and the army use this as an excuse to invade the academy – no, wait, they represent Muslims! The snag is, these pariahs don't seem very vulnerable. Beautiful, stylishly dressed and rich – budget problems are not an issue at Mutant High – they never convince as a fringe element. Like models who complain about how tough it was growing up tall and skinny, they appear bland at best, spoilt rotten at worst.

Director Bryan Singer knows how potent comic-book allegories can be – X-Men, which hurled us straight into scenes from a Nazi concentration camp, left a real bruise. His take on paranoid, post-September 11 America, has none of the same poke. Hawkish Stryker begins as an embodiment of the about-to-be fascist state; he ends as the bad apple in a wholesome barrel. Take his president, who looks uncannily like George Bush Jr. There's a nicely satirical moment where the latter is shown playing the media game ("be careful – the last thing we need is the bodies of mutant kids on the six o'clock news!"). But his harshness proves superficial. One of the film's themes involves the relationship between fathers and sons, and the need to make time for children. Right at the start, the prez says that he wants his secretary to clear his schedule, so he can have dinner with his son. Get it? All may not be well in the kingdom, but the king's solid as a rock. Lest we forget, the studio behind this film is owned by the extremely gung-ho Rupert Murdoch. Maybe Singer was worried about seeming unpatriotic; maybe he wasn't allowed to show the American mainstream in too shady a light.

For a film so concerned with Darwin's theory of evolution, there's also a lot of talk about faith. Halle Berry's weather girl Storm is permanently moist eyed, consoling new-mutant-on-the-block, Nightcrawler (Alan Cumming), a crucifix-toting, teleporting German. "I believe in you," she says. Before long, he's reciting "The Lord is My Shepherd". Can it be pure coincidence, too, that people keep saying "Oh my God"? Ben Affleck's Daredevil (a Catholic) was similarly inclined. It may well be a trend, but what are the rules? Would it have been acceptable to have Nightcrawler muttering a Jewish prayer? With regards to religion, as to so many things, X-Men 2 sets itself up as "different", while trotting out the party line. No wonder there's so little tension. Think of all the surprises in Singer's breakthrough film, The Usual Suspects. Keyser Soze would blush at such a waste of pace.

That said, there are quirky elements, bubbling away in the background. Stryker, for example, has a mutant son, Jason, brilliantly played by Michael Reid MacKay, a sunken-eyed beanpole, in a wheelchair, whose face makes you think of open graves. Jason's "gift" is essentially that of the sick storyteller, and the visions he visited upon his mother drove her to her grave. ("My wife took a power drill to her left temple," says Stryker, "in an attempt to bore the images out.") Mutant genes, we find, are passed on by the male. Jason, clearly torn between craving his father's approval and punishing him for letting abnormality into their lives, is a great study in self-loathing. He seems to have been dropped in from a Philip K Dick novel. Your heart sinks every time the camera tears itself away.

The only other person with a similar voltage is Magneto. We watch him being drugged in prison; he looks exhausted, the bags under his eyes as juicy as slugs, but it's still shocking to see his erect figure crumple. Later – in the film's most eerie visual set-piece – he escapes, by draining iron from the blood of a guard. A junkie receiving a fix couldn't look more exultant, his mouth twitching at the delicious inevitability of it all – his life and liberty won at the expense of the guard's. McKellen never downplays the ruthlessness of his character. He simply makes you understand it. At one point, flame-throwing teen Pyro, notices Magneto's helmet and calls it "dorky", which fazes Magneto not at all. He has no need to prove himself a "winner", no need to power-dress. He's supposed to be the elitist, the latent fascist. But in so many ways, he's the film's one true democrat.

If only there was more such ambiguity. Singer has fought to keep hold of this franchise; maybe he should just bail out. Compromised and piecemeal, his film seems almost solely designed to help Fox win the battle with Warners, whose Matrix sequels are now due. A few years back, Singer was widely tipped as the rising star of US cinema. Today, he seems locked into the mainstream, his thunder taken by the likes of Paul Thomas Anderson, David Fincher and Spike Jonze... even The Matrix's Wachowski Brothers. Children stand around in playgrounds, trying to decide which superhero they'd most like to be. Film students do the same with hot-shot directors, those lucky creatures who possess a vision of their own. Bryan Singer – rich and increasingly anonymous. Who'd want to be him now?