The movie begins with a demonically possessed girl tied to a wooden post and set afire by her father, who wants to free her soul. He's accompanied the locals and one of them, who reads out of an ancient "Book of the Dead".
Then, the scene shifts. David, a twenty-something guy who has been living in Chicago, meets up with a few old friends at a secluded cabin in the woods. He's there to help his younger sister, Mia, detox from her drug abuse. However, they all resent him. Mia does because she feels he abandoned her to their crazy mother, who recently died. His friends are angry at him because he's been out of touch with all of them. As the evening goes on, and Mia starts going through withdrawal, things get worse. She insists she smells something rotting--and when they discover the trap door in the floor and go down into the huge cellar, discover a room filled with rotting, dead cats hanging from the ceiling. This is also where the girl was burned alive in the opening scene. Mia ends up fleeing and is the first to get possessed by the demon, called "Kunda". One by one horrible things happen to the rest of them. The last half hour consists of four different "endings", all of which are unsatisfactory.
Evil Dead touches on elements from the first movie but has the feel of Cabin Fever. In fact, if I hadn't known this was an Evil Dead remake I would have thought it just another similar horror movie that had a few things in common. It's that different.
I also didn't like that they made the evil entity "Satan". In this version of the book of the dead there are goat headed humans and pentagrams and "Satan" written on the pages, rather than the original Book of the Dead (created by Tom Sullivan) which seemed to have Cthulhu-esque origins, which is way cooler.
If you're a fan of the original, particularly if you are old enough to have seen the original in a theater, then you're going to be disappointed. Each of the original three movies are better than this redo.