Desire is the cause of the all suffering. This is what the newly enlightened King Siddartha came to believe. Nowhere is this more epitomised when you look at drug addicts going through life seeking only their next fix. The immense physical and psychological dependence causes great suffering and that's the moral behind Requiem for a Dream, one of the most intense movies I've seen.
The film is clever in how it makes its point. For the first half, the story could be considered to be a glorification of drugs. It illustrates very effectively the hallucinogenic nature of taking mind-altering substances. This is done in such an off-hand way that even people who spurn such substances might become fascinated with what the feelings experienced are like. Not so by the end.
The film focuses on four characters: Harry Goldfarb (Jared Leto) is a young slacker who wants to get out of the situation he's in along with his girlfriend Marion Silver (Jennifer Connelly) and friend Tyrone Love (Marlon Wayans) by creating a store that will let Marion showcase her fashion designs. Harry's mother Sara (Ellen Burstyn) has her own dream of appearing on a television game show. To achieve their dreams, they both go to great lengths which results in them being so addicted to various substances that all their actions are dictated by their desire for the drug, not the original dreams.
The film works on two levels: on the one hand, the protagonists are addicted to their dreams and desire it (this sort of an addiction can actually be positive, assuming the desire is for something non-material). To achieve their desires, they take a path that makes them addicted to physical substances. In both the cases of the mother and the kids, it is excess use as well as withdrawal that causes them to make choices that they find it hard to live with (which leads to a depressing ending).
Director Darren Aronofsky (who also did the amazing Pi) doesn't hold any punches in his adaption of Hubert Selby Jr.'s novel. He employs several camera tricks to present the audience with a visceral feel for what the addiction lifestyle is all about. This includes the depiction the getting the actual fix (from cutting the substance to the pupil dilation), the various camera lens distortions to produce an hallucinatory effect, and the split screen technique to illustrate the nature of people's interactions. The amplification of sounds made during certain periods in the addiction cycle also leads to a powerful result. The ending of the film, where the images of the four different characters flash by at an increasingly rapid pace left me drained.
The acting is excellent---it feels as though the actor really becomes the character they are portraying. Requiem for a Dream is made complete by the amazingly orchestrated "requiem" by Kronos Quartet, which was fixed much more strongly in my memory than the film itself.
While they use a lot of drugs, it is heroin that ultimately leads to the destruction of Harry, Marion, and Tyrone. Aronosky not only illustrates the lengths that people will go to satisfy their addictions, but also how it hurts relationships. In that sense, this movie is a bit like Trainspotting, but it is the intensity of the film-making that pushes it to a much higher level.
There are a lot of other interesting touches to Requiem for a Dream that are easily overlooked given its focus on the depravity of drug addiction. One of them is Freudian in nature: both the male protagonists have Oedipal relationships with their girlfriends/mother. There is also some commentary about the nature of TV games shows and the obsession with weight-loss.
In my view, it is unlikely that Aronofsky could've made this film without some experimentation into the nature of mind-altering substances (even if it involves relatively tame substances as opposed to heroin). Watching (and perhaps even making) films is in my view is a bit like taking a drug. Under current theories, dopamine neurotransmitters and receptors are probably stimulated when exposed to a drug.
In that light, this movie could be considered depressing, a downer, which depresses dopamine production. But like after listening to Pink Floyd's music and watching their movie The Wall, I came out feeling very uplifted and euphoric. The reason for this is because I'm too aware that the film itself is a contrived situation (and it's hard for me to deny my intellectualisation in this regard---everyone knows drugs are bad, mmmkay?), the sheer expression of creativity brought about by the film-makers is mind-blowing in an extremely positive manner.