The Panic in Needle Park (1971)

Grim drama set in New York, adapted from a 1966 novel by James Mills and with a screenplay by Joan Didion. 

A very young Al Pacino (in his first role) plays a heroin addict, Bobby, who introduces his girlfriend Helen (Kitty Winn) to his world of dealing and using drugs. Plot-wise, that’s pretty much it. 

We see horrible, lingering shots of the couple injecting, and we see how the drugs ruin the lives of the addicts. It’s sad and disturbing, and it’s clearly intended to be. I’m not sure why you’d want to watch the film – I certainly don’t need to see it again – but it’s expertly filmed, acted and edited.