The ending was good + surprising (spoilers)
Look I enjoyed this movie throughout, and while some things could have been a little bit better it was still nice.
The ending was awesome imo. When it turned out to be an excercise I thought: 'Ok this is ok but not as surprising as it could have been' It was simply ok but not great.
Then later in the ambulance I thought everything was over and the ending was positive. Well guess again! Because he was so stressed out before and now feeling totally safe with his wife... He had a weak moment and he accidently gave away the location...' This was, for the terrorists, basically the only way to be sure that he gave away the location, first stressed out till the max and then feeling 100% safe with your wife.
Shocking ending to be honest! The bad guys won, and guess what? That happens sometimes.
And sure we can complain about the lack of information on the terrorists or how his wife got into the terrorists organisation. But hey why care about that?
This movie is centered around a guy being held captive in the trunk of a car, all the while when terrorists are executing a master plan. This is not for example 24, where you have 24 series to explain everything.
You can't fully explain a terrorist attack on this size of scale in 80 mins of movie. So what they did was good. We had to use our imagination a bit. The movie director wanted us to think that the US was taken over by an extremely well organised terrorist organisation with contacts on the inside (unlikely to happen but possible given (the worst) a set of circumstances). And it was pretty believable to a certain extent.