Martin Fuller asks: After all that business with the crack in time, how aware are the people of Earth that aliens exist?
Steven Moffat: Yes, sometimes. No, other times. Erm. Good enough? Okay, the problem here is that if you're doing a stonking big invasion of Earth story, you don't want all the characters yawning and stretching and saying "Not again!" You want doomed fools protesting that there's no such thing as aliens, before being eaten by intelligent space badgers. It's more dramatic! And frankly new viewers (and we need them all the time) don't want to watch the show where everyone's comparing this alien invasion to the one two years ago, because it feels like you've missed all the good stuff. So the cracks in time (and actually the Time War before that) is just to give us a little latitude. To allow aliens to be scary shocks again, but still be able to justify that in... well, columns like this. In my own head, the memory of all those invasions has been misted over in most people's memories, but remains more vivid (usefully) in the minds of the people directly involved.
Да.