An outrageous comedy in which four everyday suburban guys (played by Ben Stiller, Vince Vaughn, Jonah Hill & Richard Ayoade) come together to form a neighbourhood watch group, but only as an excuse to escape their humdrum lives one night a week. But when they accidentally discover that their town has become overrun with aliens posing as ordinary suburbanites, they have no choice but to save their neighbourhood -- and the world -- from total extermination.