This movie follows the original Evil Dead reasonably faithfully while still injecting enough variation on the theme to be interesting.
The drug addiction subplot is a great touch because it adds a depth to the characters beyond "we're just here and want to bang for some reason" and touches on some backstory without delving into it ad nauseum. It's not necessary for a horror movie but it's nice to have characters whose behaviour is somewhat rationalized.
It also makes the movie more tense because Mia is the first to be possessed by the violent murderous spirits, but her transformation is less obvious because she's already screaming and telling everybody to fuck off due to withdrawal long before she starts turning into a demon. Furthermore, it gives the characters a reason to not leave immediately when things start going weird. Like, yeah, she's acting like a violent psychopath but that's probably just the heroin withdrawal talking.
The movie looks great, and although it loses the low budget charm of the original, it is approximately as gross and bloody which is nice. And if you really liked the Evil Dead series because you get your kicks watching people chop their own hands off, that happens like two times in this one, once with a turkey carver and once with a fucking jeep. So, you know, that's cool.
The first half of the movie puts along at a pretty good pace with the characters getting possessed and violently murdered one after another, but then gets bogged down about two thirds of the way through. At some point one of the characters figures out that the human hosts can be rid of their demonic possessors if they are buried alive or dismembered. They also find out that if five people die at the hands of Deadites then some big daddy demon will get released from the bowels of hell and all manner of bad shit will happen.
So with everybody else dead, Mia's brother (Shiloh Fernandez) buries Mia alive and then resuscitates her to get all the demons out, then he dies, I forget why, but anyway that's the fifth death that brings about the big daddy demon which Mia then runs away from and fights for what seemed like a really long time.
That was unfortunate because a) up until that point the movie had been a non-stop bloodbath and the whole last fifteen or twenty minutes were kind of unnecessary, and b) the big daddy demon is basically just a regular Deadite. They could have gone a lot weirder with the monster design but didn't.
That being said, I appreciate that they did diverge from the original movie, giving me a feeling of "I don't know where they're going with this anymore", and I got to see a girl with a chainsaw for a hand which I would never construe as a bad thing.
Besides that, my only major qualm with the movie was that it is a lot more serious than any other entry in the Evil Dead series, going more for straight up horror than horror-comedy. But again, that's just its way of differentiating itself rather than being a carbon copy of the original. It's the best I've seen of the latest crop of franchise reboots anyway.
All in all I found this movie super enjoyable both as a fan of the original series and as just a regular person who likes gratuitous blood and violence.
Directed by: Fede Álvarez. Written by: Fede Álvarez and Rodo Sayagues, based on the film The Evil Dead written by Sam Raimi. Starring: Jane Levy, Shiloh Fernandez, Lou Taylor Pucci, Jessica Lucas, Elizabeth Blackmore.