Avatar

First and foremost, Avatar, as promised, unquestionably represents the best visual use of performance capture and 3D technology in cinema to date. It has also been treated to one of the best marketing campaigns. Somehow, the phrase that found its way into every pre-release report, article or outright puff-piece was game changer - and that was before anybody had seen any footage. To get everybody talking about your latest project as a film that could change the face of cinema is a difficult thing, but not nearly so difficult as living up to the expectations that bravado creates. 'King Of The World' James Cameron does love a challenge.

So, is it or isn't it? Has 'the game' been changed? The answer really depends on what game you're playing. If we're talking about what a film can achieve visually (and in terms of box office receipts), Avatar is unequivocally a game changer. If the game you're interested in is the older art of storytelling, character and dramatic narrative, it is not. Looking back at Cameron's own oeuvre, the experience of reading the scripts of Terminators 1 and 2 and of Aliens is engaging in its own right, before you add any visuals. The same can't be said of Titanic and True Lies, but they do undeniably provide great opportunities for some spectacular action set pieces. Avatar, while more ambitious, leans towards spectacle over script: the story is no dud, but you will come out of the cinema talking about what you've just seen, rather than quoting the instantly classic lines of Terminator/Aliens.

It may not be crammed with soundbites, but boy, does Avatar look good. The 3D technology is the best it has ever been, and unlike gimmicky 3D where an audience might lean away from something that appears to project out towards them, 3D in Avatar is overwhelmingly used to create a sense of depth - we're looking into an open window on another world, stretching out in front of us. And what a world it is. The fruits of Cameron's audacious imagination could not be more psychedelic and eye-boggling if Mother Nature decided to reboot our ailing planet with some lush, trippy creations and commissioned a prog rock cover art specialist to make it so. Planet Pandora is awash with colourful critters and a forest of flora straight out of a botanist's acid trip.

Wonder at the bio-luminescent forest, culled straight from James Cameron's deep sea diving expeditions. Boggle at the six-legged horse beasts. Thrill to the glowing pink tree, guardian of ancestral memories. Sigh over the motile dandelion spores, giant touch-sensitive plants and rainbow pterodactlys. Coo over the many-hued sunsets. Then of course, there's the stars of the show, the blue, environmentally low-impact Na'vi whose land is threatened by a nasty corporation. If it all sounds one crying unicorn away from New Age poster art, that's because it is, but not in a bad way - most of the time it looks so glorious the sheer beauty of the thing browbeats your cynicism into submission and leaves it lying battered and bruised, face down in a pool of shimmering ethereal phosphorescence.

Our hero Jake Sully - an engaging turn from Sam Worthington - soon discovers that although it looks pretty, Pandora isn't a gentle place. There are all sorts of beasties who might look stunning, but will bite your head off given half a chance. Nevertheless, the place doesn't feel half as threatening as mean ol' boy Colonel Miles Quaritch (Stephen Lang) tells his grunts it is, perhaps because he's keen to move in and start blowing stuff up, or perhaps because this 12A film can't afford to show any close-up decapitations. This is a depiction of jungle terror you can safely take your gran to watch.

That 12A certificate is a bit of a shame come the climactic battle scenes, where Cameron's trademark talent for violence is made family-friendly. This said, there's a sort-of tribute to Aliens' powerlifter sequence that stops just short of actually using the words "Get away from him, you bastard." In Michelle Rodriguez' tough fly-girl we also discern a ghost of Aliens' Vasquez, but there's no killer banter ("Have you ever been mistaken for a man?" "No, have you?") this time around - these Marines are mostly content to simply obey the Colonel, whose arguments about fighting "terror with terror" paint a broad-brushed satire of the war in Iraq. Sigourney Weaver as Dr Grace Augustine is his loudest opponent but she rarely gets the chance to really flex those Ripley muscles.

Like Jake's part-time existence in an alien world, Avatar is a film of two halves - the military and scientific, and the environmental and mystical - which clash in the last act. Of all Cameron's work, this most recalls The Abyss, which began as submarine thriller and ended as Close Encounters Of The Submerged Kind. Certainly the glowing flora and fauna and peace-loving aliens aren't a million miles thematically from what Ed Harris found at the bottom of the deep blue sea, albeit this lot will start firing arrows at you if you piss 'em off. Avatar goes further than the The Abyss, taking the close encounter to a new level with an interspecies love story between Sully and Neytiri (Zoe Saldana) that successfully has us believing in the existence of these blue skinned giants and their capacity for love, for all that Neytiri is at times written dangerously close to Pocahontas. Still, we buy their relationship, which is arguably an even bigger ask than getting us to believe in killer robots from the future, the motherly instincts of acid-blooded aliens or Arnold Schwarzenegger posing as a normal member of society.

It is important not to lose sight of the fact that most showcases of new technology are in themselves rubbish. The technology is then refined, applied to a better film and eventually becomes standard. This is never good enough for Cameron, who always pushes boundaries at the same time as making a good film. In Avatar he both experiments with new tech to dazzling effect and creates a highly watchable, full-throttle piece of entertainment, and nothing can diminish that achievement. Still, this critic would love to see a film created using these technologies alongside a script and characters as engaging as his finest work. For many directors, Avatar would be a career best. For James Cameron, it is simply excellent work.