If psychosis is truly a necessary element in the creation of art, as Darren Aronofsky's Black Swan seems to suggest, then let us band together and thank the Baby Jesus for every nervous tic, social disorder and neurotic character trait that Aronofsky himself may have been subjected to. Because what he has created here is truly astounding, a film that once again demonstrates his ability to work in different modes while still being clearly and recognizably himself.

Natalie Portman is already drawing serious Oscar buzz for her role as Nina, the emotionally frail but physically gifted ballet dancer at the center of the story. Despite being well of an age where you have expected her to have moved along, Nina still shares an apartment with her slightly off-kilter and over protective mother -- played brilliantly by Barbara Hershey -- her bedroom appearing not to have changed since childhood. Mom was a dancer herself in her youth, a career she abandoned to have and raise Nina, and she is clearly living out her own fantasies through her daughter.

Though a hard worker Nina has been stuck as a secondary player in her ballet company, a supporting part in the orbit of the older dancer -- played by Winona Ryder -- who she worships from afar. Or, at least, worships until the head of the company (Vincent Cassel) decides it time to play out with the old and in with the new, forcing the incumbent into retirement while announcing a new revival of Swan Lake as the showcase production to launch a new talent. But who will that talent be?

Though Nina's emotional distance nearly costs her the lead it eventually falls to her, which should be cause for celebration but very vocal doubts about her ability to be as seductive as the role requires, coupled with the extreme work load and the favour heaped upon new arrival Lily (Mila Kunis), combine to heap pressure upon pressure on Nina until her frame - and mind - threaten to crumble beneath the weight.

Adding some giallo influences into his palette, Aronofsky treats Black Swan as a slowly building psychological thriller with Nina's outward signs of stress -- a tendency to scratch herself until she leaves marks -- slowly transforming into increasingly internal signs of mental collapse and surging paranoia. Physically isolated from her fellow dancers in what is meant to be a mark of prestige -- a move to the principal dancer's private dressing room -- Nina is soon emotionally isolated as well and left grasping at straws as she sinks under the weight, increasingly unsure whether she can trust her colleagues and -- more disturbingly -- her own senses.

Through the course of the first two acts, Black Swan is an admirable but not particularly exceptional piece of work by Aronofsky's standards -- which is to say it's better by far than most films despite following a fairly predictable and stable path, one mostly notable for the physical dedication of both Portman and Kunis who appear to do a great deal of their dancing themselves. Cassel delivers a restrained but compelling performances as Nina's taskmaster, Mila Kunis provides a shot of sex appeal, and Hershy the sense of someone unstable enough to keep things interesting while Portman herself plays simply as frail, frail, frail. But when the turn comes into the final act it quickly becomes clear that all bets are off, nothing is sacred, as both Aronofsky and Portman swing for the fences and clear them with ease. It's hard to say which is more impressive, really, the audaciousness of what Aronofsky demands of Portman or her ability to not just meet but exceed those demands.

Yet another potent effort from a director who has yet to put a foot wrong, Black Swan once again makes the argument that when it comes to the young generation of US film talent Aronofsky stands head and shoulders over the vast majority of his peers. Simply astounding.