Invasion is a made-for-TV science fiction drama based on a story by Robin Cook in which tiny rocks have fallen from the sky and, when they are touched, trigger dormant viruses in humans. These viruses turn the humans into aliens whose goal is to transform all of the other humans on Earth. The newly transformed aliens succeed by infecting large numbers of humans with incredible swiftness, all of whom are ready to turn the planet over to its new alien overlords. There are only a few humans left on Earth with sufficient medical knowledge to combat the virus, and they’re quickly running out of time.