And so, it’s finally here. After five massive tent-pole movies, launching four separate but connected super-hero franchises, the Avengers have finally assembled. Has it been worth the wait? Emphatically; YES.

Marvel Avengers Assemble – to give the film its official UK title, in case anyone was seriously expecting to see Steed and Mrs Peel back in cinemas – sees the culmination of Samuel L. Jackson’s Nick Fury’s long-held ambition (going back to the end of the first Iron Man movie) to gather the Earth’s mightiest heroes together into a team, capable of defending the Earth against any threat it might face.

The Avengers is one of the comic-book world’s most beloved franchises, and ever since the extent of Marvel’s ambition as a film studio became clear, there have been fears that it couldn’t be done. How could it be? All of those huge and fantastic characters brought together in one universe; all of those big-name stars vying for room in one film, all the while staying true to the brand’s comic-book roots?

It didn’t seem possible. Then they hired Joss Whedon. It’s well established that the Buffy creator can handle a large ensemble cast (just check out any of his television works), and he proves to be an inspired – and brave – choice to direct the biggest blockbuster of the summer.

Whedon’s scripts have always had a sense of the comic-book to them, maintaining a sense of fun even when things get heavy, and he’d already proved he could handle a big budget action flick with the wonderful Serenity, but it’s quite another thing to pull together so many different characters, established under so many different directors, into something coherent and tangibly his own. As it turns out, it’s quite possible that Avengers Assemble is Joss Whedon’s masterpiece.

If you’ve never read an Avengers comic book, or seen any of the previous films for that matter, then don’t worry; you’ll have no trouble enjoying this one. The film spends the first half hour or so catching up with each of our heroes – Mark Ruffalo’s Hulk, Chris Evans’ Captain America, Robert Downey Jr.’s Iron Man, Scarlett Johansson’s Black Widow and Chris Hemsworth’s Thor – and the characters are so well drawn and so well played by the assured cast that you immediately have a sense of who everyone is.

From then on in, the film is a relentless, breathless rollercoaster ride, with the vibrant action refreshingly taking place primarily in the daylight (it’s nice to see a film not obsessed with being literally dark), but, crucially, it’s a ride that never loses its grip on the characters.

Even right in the thick of things, Whedon’s confident direction ensures that the character beats continue to drop and that everyone behaves in a way that’s appropriate to their character. Everything is measured perfectly, never descending into the mindless CGI mess that the likes of Transformers are often guilty of.

Of the characters we’ve seen before, it may come as a surprise that the formerly problematic Hulk (here in his third incarnation within a decade) is arguably the film’s stand-out player. Mark Ruffalo is a better fit for the role than either Eric Bana or Edward Norton, looking appropriately bookish (it is Doctor Banner, after all), and his tender, somewhat nervy portrayal finally sees someone make the role their own. And when he gets angry, the Hulk himself has never looked better – nor been scarier! (Although he is also responsible for the film’s more overtly comic, slapstick moments.)

Elsewhere, the established players reprise their roles with ease, with Scarlett Johansson’s Black Widow a more natural fit here than she was when shoe-horned into Iron Man 2, and Jeremy Renner’s Hawkeye making a solid impression as the only hero we’ve not really been introduced to.

Tom Hiddlestone’s conniving Loki, first seen in Thor, returns as the film’s primary antagonist, and Hiddlestone continues to have a ball in the role, giving us a fantastic, near-pantomime villain that you can’t help but love to boo and hiss.

And if you are a comic-book fan, then this is going to be very special to you. The previous Marvel films, whilst getting most things right, still felt like films of comic books. Avengers Assemble is a comic-book film. It’s as if the pages had come to life before your eyes.

During one bravado sequence towards the end, with all our heroes assembled, and fighting tooth and nail to hold back a Loki-led alien attack, Whedon treats us to an extended and unbroken tracking shot, as the camera zips around the embattled city and closes in on each character as they demonstrate their particular skill-set in defence of our world. It’s so joyously assured, so spectacularly confident and so giddily entertaining; it’s the moment when you realise that this is exactly what it always looked like in your head.

The CGI is brilliant; the script smart and witty; the action exhilarating and the characters spot-on. Fans would never have believed it was possible to make an Avengers film that truly captured and translated the experience of reading the comics into a film, but, remarkably, that’s what Whedon and co have achieved.

Avengers Assemble is – and we make no apologies for this – an absolute marvel.

Released in UK cinemas on Thursday 26th April 2012 by Walt Disney Studios Motion Pictures UK.

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