In Ridley Scott's 2012 sci-fi film "Prometheus," a group of astronauts travel to a distant planet, guided there by a series of ancient cave paintings discovered on Earth. It seems that tall, godlike aliens visited Earth many thousands of years ago and left a map that humanity would eventually be able to follow back to their homeworld. It might have taken us several millennia to develop long-range space travel, but we eventually have the wherewithal to follow the map.

Of course, when the astronauts arrive, they find strange, brutal things they can't understand. The tall godlike aliens, which they nickname Engineers, are all dead, having been killed by a menagerie of genetically engineered critters of their own making. Some unusual evidence leads the astronauts to believe the Engineers were preparing to travel to Earth with a cargo of killer monsters, hoping to seed our planet with them and kill us all.