By and large,I agree with the precedent user :it's a bit a missed opportunity.
When Louise is alone in her room ,hearing screams and shots ,we do feel her terror : we are caught in this macabre hide-and-seek ,we are shivering :the treatment recalls sometimes "panic room",but with a big difference:during Louise's terrifying ordeal,we never see the terrorists ,only their shoes in the corridors ,and our fear is all the more intense since danger remains faceless while making its presence felt every second.
By the same token,the scenes with Giovanna ,the woman on honeymoon,are full of emotion and human touch ;both women stand by each other,and it helps them get through their nightmare .The moment when they embrace each other is perhaps the most moving in the whole movie.
(Now,I'm speaking of the actors and obviously,not of the real life characters)
It may be the directing or the script,but the father figure is a namby -pamby man, his wife ,a woman who sings lullabies (which infuriates her daughter ,and considering the impending fire,who should have known better);as desperate parents ,they fail totally to convince ;one could add that in the first part ,Louise appears as a spoiled child ,not particularly endearing ,and we only side with her in the second part.
The first part is mostly filler : a tour in Bombay,please remember the guide!
As the Greek user already pointed it out ,the third part is desultory ,and we could easily do without it;only the phone call to Pierre makes sense .
It would have made an excellent 45 min movie;artificially stretched out ,it does not make it as a 90 min one.
Watch it anyway:its central part will scare you to death.