Evans' son has joined the alien mothership and she's determined to bring him back.

Pretty heavy weaponry for guarding a refugee camp -but pretty light armament if you're thinking of taking on an alien mothership.

But to start with, in this film our heroes need to overcome a 3,000 mile wide alien mothership.

But then there's the computer virus that Jeff Goldblum uploads into the alien mothership, that is ultimately what allows the humans to defeat the invaders.