The alien invasion or space invasion is a common feature in science fiction stories and film, in which extraterrestrial lifeforms invade the Earth either to exterminate and supplant human life, enslave it under an intense state, harvest people for food, steal the planet’s resources, or destroy the planet altogether.
The invasion scenario has been used as an allegory for a protest against military hegemony and the societal ills of the time. H. G. Wells’ novel The War of the Worlds extended the invasion literature that was already common when science fiction was first emerging as a genre.