The Autopsy of Jane Doe is a movie with a lot of promise. The first half of the movie is quite compelling and atmospheric. ALERT: SPOILERS. If you don't want it spoiled for you, you should, because it sucks. These are the reasons why:
1) All of the tense, mysterious buildup creates goodwill with the viewer, which is thrown out the window when things become overtly supernatural in the second half. And it's not even good supernatural. In fact, the average episode of CW's Supernatural is scarier.
2) The first half sets up the promise of explanation later on. However, when the explanation rolls out, it makes no sense. Jane is a witch? So, why did she kill the girlfriend and why didn't she really use that illusion power to her advantage? What did she glean from freaking out the father and son, not actually getting them hurt, all the while letting them dissect and burn her? When she finally does hurt the dad, why do her eyes un-cloud only to become cloudy again? I thought for sure she was transferring her paralysis to the dad by hypnotizing, but nope. And why was her ability to mark skin only used on the father? In general, why doesn't she use whatever powers she has to her advantage in smarter ways? Is the singing voice someone controlling the whole situation from the outside? If so, who and why?
3) I like Emile Hirsch and Brian Cox, but their acting is surprisingly spotty. They don't seem very freaked out when the undead begin pursuing them. Shock, disbelief, and many uses of "what the fuck is happening," would be appropriate responses. Although, I suppose this once again is mostly a bad writing issue.
Sorry if you liked it, but raise your standards. Scary horror should be scary. Horror that sets up rules needs to stick by them and make some kind of sense. The audience isn't all stupid.