Flying saucers have been reliably seen over the capitals of the world, and the whole world awaits with bated breath to see what will transpire. Among those waiting is the President of the United States (Jack Nicholson), who is assured by his science advisor (Pierce Brosnan) that the coming aliens are utterly peaceful. This advice is hotly contested by the military, who advices the President to annihilate them. When the aliens land, they are seen to be green, garish, and very cheerful. But appearances prove deceiving when the 'friendly' aliens abruptly disintegrate the entire U.S. Congress. Hollywood notables appear in vast quantities in roles (and sub-plots) of all sizes in this zany feature.