It's grand, expensive, and currently stands as the highest grossing film of all time. With Avatar, James Cameron proved himself to be the master magician, the David Copperfield of Hollywood, and his 3D fantasy epic is his multi-million dollar conjuring trick. And nine months on from its initial run at the box office, it's back, in a newly extended Special Edition.

Never a particularly concise film to begin with, this new edition of Avatar is nine minutes longer, and puts back a few scenes trimmed from its initial release.

While shoving Avatar back into the globe's multiplexes so soon after its initial showing could be viewed as cynical profiteering, James Cameron's florid fantasy is a film that relies so heavily on its visuals that the cinema is inarguably the only place to see it. Viewing it in 2D, on a television at home with a cat on your lap strips the movie of much of its glittering impact.

And so Pandora returns to the big screen in all its luminous glory. Essentially, a digital playground in which James Cameron plays around with the pet themes familiar from his earlier movies (space marines, heavy artillery, ecological warnings, destruction on a grand scale), the planet is home to the rangy, tree-dwelling Na'vi, whose verdant forest is under threat from a greedy corporation and its high tech army for hire.

In an effort to win the locals' ‘hearts and minds' (one of the film's many heavy-handed references to real-life conflicts), scientists have engineered avatars, creatures identical to the indiginous Na'vi, but that can be controlled remotely by humans lurking in special chambers.

Jake Sully (Sam Worthington) is a crippled ex-soldier who, linked to his Na'vi alternate body, becomes emotionally attached to the residents of Pandora, and finds himself fighting alongside them in a desperate guerrilla war against the invading humans.

You'll know all this, of course, because you'll have seen the film already. If so, Avatar's numerous shortcomings may still linger in your mind. The clod hopping ethnicity of the Na'vi and their toe-curling cod religion, the forgettable script and pulpy, predictable story are all as distracting the second time around.

After an engrossing introductory half hour or so, Cameron spends a lengthy second act swooping his camera across Pandora's tropical paradise, and swooning over Jake's relationship with Neytiri (Zoe Saldana). There are endless scenes of horse riding, flying and hunting, and the newly added sequences, which are almost interchangeable with those already present, make this part of the film even flabbier than it was before.

When the confrontation between human and Na'vi finally arrives, however, it's with a familiar Cameron crunch. His movies may have become soppier in recent years, but he's still an action director at heart, and the climactic battle, where the residents of Pandora swoop upon the armoured might of the humans' military machine, shows some of the verve we perhaps took for granted in Terminator 2 or Aliens.

This darker aspect of the film is helped considerably by Stephen Lang's performance as Colonel Quaritch. While forced to play a fairly stock military villain, he brings considerable heft and vigour to the role and gives every scene he's in a tingle of steely-eyed menace.

But these are all compliments that could be paid to the original cut of the film, which brings us to the central problem with Avatar: Special Edition - the additional footage is largely inconsequential.

The much discussed scene of alien copulation is mere seconds long, and is far less steamy than some were probably hoping. Elsewhere, there's an extra hunting scene, a brief sequence that shows an early retaliation from the Na'vi, prompting Colonel Quaritch's tree-wrecking expedition. Perhaps the most notable new moment occurs close to the end in a mercy killing that adds more melodrama where the end credits should be.

As opposed to, say, the extended cuts of Aliens, Terminator 2 or The Abyss, the new scenes add little of particular note to everything we've already seen. There's nothing here of the magnitude of The Abyss' excised tidal wave, or even the trimmed sentry gun scene of Aliens.

And, unlike those earlier science fiction classics of Cameron's, Avatar has had almost no time to percolate in the collective geek consciousness. By the time Aliens: Special Edition came out many years after its initial release, fans of the film were positively champing at the bit to see it in its new form.

Avatar, on the other hand, is still comparatively fresh in its audiences' minds, and those returning to their local multiplex expecting to see a startling new side to Pandora are almost certain to be disappointed.

Instead, what we've been given is a second chance to see Avatar on the big screen, with the added bonus of a few more minutes of flora and fanciful creatures. And while Cameron's conjuring trick of cutting edge 3D and sumptuous colour may not have quite the shock-and-awe impact it had the first time around, it's an entertaining sideshow nevertheless.

See also:
Resident Evil Afterlife 3D impressions (uses Avatar technology)
The directors for and against 3D technology
7 notable old-school 3D effects