Beware yonder (mild) spoilers.
Here's the hook of this movie: what if those paranoid right-wing conspiracy theories of the depravity of the liberal elite, like the notorious PizzaGate scandel, were real? The conspiracy, in this case, is an uncovered chat thread between a bunch of L.A. media types making a joke about hunting conservatives for sport in an isolated location called 'The Manor.' The text thread is uncovered and goes viral amongst far right 'media' and all the people in the thread lose their jobs or other positions in the media. This eventually leads to them making the hunt a real thing.
Most of the rest of the movie is a cat-and-mouse game between broadly drawn conservative stereotypes and broadly drawn liberal stereotypes. The conservatives are all stupid, violent, racist gun nuts who say "snowflake" and "cuck" all the time and the liberals are all snotty, sensitive, condescending, and can't take a joke.
And then there's the lead character, Crystal. She doesn't join with the rest of the hunted, she doesn't get fooled by any of the traps that the hunters prepare, she's independent and capable, but she's also possessed of a straightforwardness, a dark sense of humor, and a strange sort of sadness. She's actually one of my favorite characters in recent years. I'd like to see more of her. She's matched by Hilary Swank as Athena, the organizer of the event and type-A alpha badass who chews scenery with such manic glee that you kind of wish she had more screentime.
Because the movie is so broadly drawn and farcical it feels less like a series study of political divide and more like a hyperviolent version of that old Mad Magazine cartoon Spy vs. Spy, where two spies attacked each other in an endless, meaningless war. This does run at odds with the way the film is marketed, which makes you think that the movie will have something profound to say, but it's really just a big dumb cartoon.
According to the Wikipedia page, the working title for this film was Red State Vs. Blue State, which should kinda tell you everything you need to know about the angle they were going for. It was pulled from its original release date just after one of our endless stream of nasty massacres, so it makes the movie look more timely than it actually is. Still, if you can take a joke and wanna just see a bunch of big dumb violence with a great hero and a great villain then you need to go check this out. I kind of hope it becomes another lunatic franchise like The Purge.