Possibly one of the most disturbing films you'll ever see. The tale of four drug addicts and their lives spiraling out of control is told with vicious realism. The musical score is amazing and sets the tone for the entire film, while the song 'Lux Aeterna' is used repeatedly, it never loses it's impact.
The film is packed with outstanding performances from all the actors involved, but what really sets this film apart is the editing. Each drug sequence is visualized through a series of quick-cut images of the process, to shift focus away from the drug-taking itself, focusing on the effects instead.
The film is dark, depressing but important and honest. It is more a film about addiction and the dangers of that, opposed to drugs themselves. Addiction to television, food, love, and money are all (slightly more subtly) addressed and all act as catalysts on the junkie's self-destruction. The television fuels the desire to look good, and becomes an obsession, the fridge acts as a fierce monster if you resist it, love drives characters to do foolish things, and money drives the characters to maintain their illegal lifestyle. The visuals, sound, directing, and acting are all key players in making this a powerful, well rounded film that is important and terrifying all the same.