This flick is tricky. It deludes you think it's good because it has this great performance by Will Smith, but aside from that it's just full of lousy CGI and plot holes. Watch THE LAST MAN ON EARTH instead.
I liked about 10 minutes near the end of this flick when Cruise was in the alien ship. Apart from that it was a monumental waste of time and money. Why not take what's spent on trash like this and divide it up among film makers like Maurice Devereaux, Jet Eller, etc. so we can have twenty films that are worth watching instead of one that just lies there and stinks up the theater?