Co-screenwriter David Koepp, a longtime Spielberg collaborator (think Jurassic Park), explains that they wanted to avoid the over-popular cliches.

'We made a list of things we felt we shouldn't have in the movie,' says Koepp. 'No destruction of famous landmarks, no shots of Manhattan getting the crap kicked out of it, no generals standing around a large map pushing ships with sticks into place, no TV news crews photographing destruction...'

And then the director delivers the biggest twist there is:

'And no Martians,' Spielberg announces. 'We've been to Mars and we know that nobody's there.'