Regardless, I thought the second act was a little bit of genius, and something it would be worthwhile for all writers to see since they managed to generate so much tension, and so many emotional story beats, out of two people sitting next to each other on a plane.
One thing I've always believed is that there are two ways to up the stakes in entertainment and find new ways to wow an audience:
- Blast people with more spectacle and larger scope.
- Move in tight and focus on something small, but make it intensely important to the people involved.
Too much of either and you'll eventually start losing audience; perhaps that's part of the reason The Island and Stealth had problems this summer, even though films of similar quality have done well in the past.
Red-Eye (and, actually, War of the Worlds) does the latter and I think they both benefitted.
In my writing I like to mix both in the same screenplay -- offset large, gory action set pieces with tight, minimalist suspense beats.