(M) ****

Director: Matthew Vaughn.

Cast: James McEvoy, Michael Fassbender, Kevin Bacon, Rose Byrne, Jennifer Lawrence, January Jones.

YET another superhero movie... but hold your groans, people - this one is pretty damned good.

One of the best things about this prequel to the Hugh Jackman-starring X-Men series is that it almost wipes away the bad memories of the dire X3 and the average X-Men Origins: Wolverine, returning the franchise to the glory days of its first two films.

But that is not what makes it great, it's just an added bonus. The key ingredients here are the same as in any film - a great cast, a well-paced script that doesn't treat its audience like idiots, some deeper ideas and themes, and a welcome amount of dramatic tension.

The key to First Class is the relationship between Charles Xavier/Professor X (McEvoy) and Erik Lersherr/Magneto (Fassbender) - something hinted at in the previous films but fleshed out further here.

While Professor X is hoping for a world where super-powered mutants can live in harmony with humans, Magneto is distrustful of humans and believes mutants to be superior beings. This dichotomy is displayed brilliantly thanks to the sharp screenplay and the skill of McEvoy and Fassbender, and even though we know where these characters end up, seeing how they get there is deeply satisfying.

Their meeting and subsequent falling out is played out against the backdrop of the Cuban Missile Crisis, orchestrated in this alternate reality by ex-Nazi mutant Sebastian Shaw (Bacon). As the CIA grapples with the revelation that mutants walk among us, its up to a fledgling team of genetic aberrations to save the day and stop Shaw's plan of starting World War III between the US and the USSR.

As with any origin story, there is a lot to cover, and First Class sets up everything elegantly and swiftly. While many of the characters are merely powered cyphers (Azazel, Emma Frost, Havok, Darwin, Angel, Banshee and Riptide), the likes of Mystique, Beast, Shaw, Professor X and Magneto are well fleshed out, with the latter two being incredibly intriguing characters as the younger counterparts of what Patrick Stewart and Ian McKellan would produce later.

X-Men's main appeal has always been its bevy of specifically souped-up humanoids, and the cast of characters on display, and their CG-aided powers, don't disappoint. But the comic books underlying themes of prejudice, bigotry, civil rights and fear - so effectively used in the first two films - are the heart of these stories, and First Class doesn't forget that. While some comic fans will be disappointed by the major tweaking of the source material - Banshee isn't Irish, Mystique's backstory, Moira McTaggart isn't Scottish, the original X-Men line-up differs dramatically - the best suggestion is to check you inner Comic Book Guy at the door and revel in the way this plays into the existing X-Men movie universe.

There are flaws - Jones' acting is sub-par, there's a weirdly edited training montage, and a few cases of bad-action-movie-style dialogue, but for the most part this is pacy, punchy, smart and filled with memorable moments - including a great two-word cameo from a much-loved mutant. First Class passes with flying colours.