I tell anybody who will listen (which is pretty much just one guy, my neighbor Dave, who talks movies with me on the porch sometimes when he’s not chasing squirrels in his yard with a hatchet) that the most important element of film noir is not the lighting, the hats, the complicated plot or the femme fatale.
The most important part of noir is that all of the pivotal characters are DOOMED.
None of these people have a chance at happiness. They’re on a road to ruin and there’s no possible way to turn back. Maybe they have an inescapable past that still needs reckoning. Maybe they fumble into a bleak future. It doesn’t even need to be their fault. It just has to be certain.
And in the stark and simple Blue Ruin (great title), it’s as certain as it gets. There’s barely even a music score here. We don’t need one. We see the ace of spades right away. When dumpy schlub Macon Blair here avenges the murder of his parents by killing the man who was convicted of it, and released after a short sentence due to a plea bargain, he seals his own fate, too. He doesn’t even try to make it a perfect crime. He stalks his target straight from the prison gates, stabs him at the first awkward opportunity and then barely manages the getaway. Clumsy, impulsive and inept with a gun, he’s the sort of guy who has no business playing around with this kind of danger. When he does, fate’s claws sink deep.
What keeps him going (other than hopeless survival instinct) is a droplet of information afterward that hints that he might have killed the wrong man. There’s also the sudden realization that he may have put his sister at risk for retribution from the ex-con’s dangerous family.
The sister has the best line in the movie when she looks at her walking dead man brother and says something like “I could forgive you if you were crazy, but you’re not. You’re just weak.”
Sounds like a perfect noir “hero” to me.