If Requiem for a Dream had a narrator, we'd hope he'd repeat "don't do that" again and again until the characters put down the drugs and walked away.

But it doesn't have a narrator. Requiem for a Dream has no voice of reason. Instead, it's told through the POVs of its four main characters—Sara, Harry, Marion and Ty. One of these characters is always on screen. So if you want to stare dreamily at Jared Leto's luminous pale skin for roughly a quarter of 90 minutes, you're in luck.

By focusing on these four characters, Aronofsky intentionally never shows us what's going on outside their narrow viewpoint. He wants you to live as if you are them, which is why the ending is so. difficult. to. watch. It's like it's happening to you, because you've lived with these characters for so long.

Sometimes two characters' viewpoints are presented through the use of split screen. This is evident in the film's opening scene, when Harry takes the TV and Sara hides in the closet. One side shows Harry removing the TV, and the struggle he has, physical and emotional, when he sees that his mother has chained the TV to the wall.

The other half of the screen shows Sara in the closet, in case you didn't know what the inside of a closet looked like. (It's dark.)

Another subjective filmmaking technique Aronofsky uses is the Snorricam. (Source) This isn't because they movie puts you to sleep. (If you fall asleep during this movie, you must lead a really intense life.)  he Snorricam is a body-mounted camera invented by the Snorri Bros. They say it "provid[es] an unusual sense of vertigo for the viewer." (Source)

They mean that as a selling point.

Aronofsky popularized the use of the Snorricam, which prophesied the ubiquitous selfie stick. In Requiem, each main character pretty much gets their moment with the Snorricam. It brings the view in super-duper close during their most traumatic moments. Ty's Snorri'd when running from the cops. Marion's Snorri'd after sleeping with the sleazy shrink for money. Sara, when she's fleeing the demon fridge. The up-close-and-way-too-personal camera angle makes these already intense scenes almost impossible to watch.

But Jared Leto never gets to wear it. Maybe he's too pretty to be seen that close.