Warning Spoilers
I really enjoyed this a lot, it was a gritty true life feeling film. Until they destroyed it with that tacked add-on happy Hollywood ending.
The entire way they handled the ending is where this film jumped the shark. A Hollywood standoff at the abandoned factory. A more realistic satisfying true ending would have been just for the guy to shot the sister and kill her while stalking her, avoiding the whole ransom cops waiting outside cliche.