in this movie, the humans and the machines are at war. the machines have taken over everywhere except for the city of zion, which is buried four kilometers below the surface. in this world, the machines have created the matrix, which looks like the real world but it is a trick. a few hundred humans have been "unplugged" and see the real reality, which is dark and barren. the humans find out that the machines are digging to invade that area and they want to stop it.