The main thing this initially slow-burning horror has going for it is the fact that it is almost constantly genuinely unpredictable, but it's also one of the most uneven (promising) films of recent years; the best bit is the fantastically enigmatic, truly interesting first-half of the second-act in which the eponymous autopsy is carried out (with tangible grisly detail yet unexpected forensic accuracy) and the body's numerous mystifying mysteries are revealed, and the worst is pretty much everything after once it all goes off the rails and dips into more traditional, less engaging generic genre fare - it's a good job that the direction is pretty phenomenal for most of the piece and that the central father/son relationship is both believable and effecting, otherwise the whole piece would sink. 6/10