You’ve seen that thing on Netflix, right? The one where there’s a murder and it really seems like the guy who ended up getting prison time for it got railroaded? Totally unbelievable, totally fascinating. And the guy was actually exonerated because of the filmmaker’s work. Wait, which one are you talking about? I’m talking about The Thin Blue Line.

If you Making a Murderer fans haven’t seen it, then you really should stop reading this right now and go watch it on Netflix streaming, or at least add it to your queue. Making a Murderer would be nearly inconceivable without it.

Documentarian Errol Morris already had a couple of films to his credit, including the equally great, completely different Gates of Heaven, when he got interested in the case of Randall Adams. Adams had been sentenced to die in Texas for the murder of Dallas police officer Robert Wood during a traffic stop in 1976, and like most Death Row inmates, he protested his innocence. As Morris looked deeper, he believed Adams’ story, and suspected that David Harris, the man who had fingered Adams, was the one responsible.

Morris had already adopted one of the techniques which has defined his work: Sit people down in front of a camera, get them talking, and they’ll tell you everything. His interviews with Dallas police and the judge in Adams’ trial capture their smug certainty that the long-haired “drifter” with no criminal record was a callous cop killer, while interviews with Adams’ defense team capture their well-meaning inability to get anyone to consider Harris, a teenage criminal prodigy who stole both the car and the gun used in the crime. Adams tells his own story with a wealth of convincing detail, simmering with barely concealed anger and frustration. A string of dubious eyewitnesses undermine their own trial testimony in front of Morris’ lens. Meanwhile Harris, interviewed in prison orange due to a subsequent murder conviction, subverts his boyish looks with his dead eyes and his blasé, fuzzy account. In the end, Morris leads him to all but admit on tape that he murdered Wood.

But more than offering mere talking heads, The Thin Blue Line revolutionized true-crime tale-telling and the documentary film itself. Morris used artful re-enactments to depict the crime and the differing accounts of it, including the most beautiful shot of a chocolate milkshake spilling on a gravel shoulder that you’ve ever seen. Morris’s cinematic approach establishes chilling atmosphere and an apt visual representation of the fungible nature of The Truth, and it’s just one of a series of inventive storytelling techniques deployed that are now so common as to be invisible. He not only created a masterpiece, he eventually cleared an innocent man. Essential viewing.