Ends poorly
It's a real shame when writers apparently leave the ending until last, and then struggle with it.
Everything up to the final reel of this film is brilliant, clever and creepy. It plays as much on the racism of its onscreen characters as it does the racism of its audience (no matter how liberal you think you are).
But that final reel... wen you finally discover what's going on, it's just not plausible. But hey, you decide you'll swallow that and see how things unfurl... but all we get are a few brutal killings with 2 doses of the old "well they looked dead, but now they've come back for a jump scare" cliché. And then the very final deus ex machine... well, it deserves some explanation really. A lot of explanation. It feels as if a large chunk of the movie was ripped out, just to make it more of a surprise.
And, minor spoiler... the racial angle? Why are black people the target? Never really explained at all.
Finally... unless you're American, you're probably not going to have the faintest idea what/who the "TSA" are. My advice is you look that up before watching, because it's a sort of running joke throughout.