This movie is Life of Pi for horror fans. If you watch it less like a horror movie and more like a modern reimagining of Dante's Inferno meets Life of Pi, you will probably have a really good time.
Heavily symbolic, very deep below the surface, it has a very intense message about dogma vs. spirituality. SUPER GOOD! But very much a movie you have to think about and really digest. It doesn't spoon feed the audience at all.