The next important thing for a good disaster movie is that the heroes should save people; not everyone by any means, but a respectable fraction of those imperilled, say one out of 100 at the outside. Given the global nature of this disaster, the ratio of the saved falls to around 1:1,000,000, and since that one is the personable - but hardly magnetic - Jake Gyllenhaal, as Jack Hall's son Sam, it is hard to see the virtue of the exercise here.