Great film
I had to see this after seeing Green Inferno, and I think Eli Roth is my new favorite director. One, he knows how to cast very attractive women. Two - he keeps you guessing by not being afraid to deliver a dark ending.
For all the people saying the fireman's turnaround makes no sense - it makes perfect sense. The criminal was hoping to escape the area by pretending to be a fireman, so he had to act like a fireman (a good guy) in order to get out of the area. However, once his cover was blown, he couldn't let the girls escape since they might have reported him.