7. Original Soundtrack
Expanding on the sound design, the filmmakers were faced with another gutsy decision; do you leave 90% of your film silent or do you hire a composer to create a pulse-pounding score that heightens every waking second of the tension? The decision was made to go with a full blown musical score by Stephen Price (who has worked on epic projects before, such as the Lord of The Rings franchise) and, my God, is it wonderful. I think the largest testament to how well executed the score is composed is that over the credits, 4-5 different tracks play, with each one staying in your head. The ending sequence is just utterly amazing, and worth buying the soundtrack for alone.