9. The Case of the Ancient Astronauts

NOVA investigates the theories of von Daniken and others that the Earth has been visited by intelligent beings from outer space. Among claims examined are: that the building techniques used in the Great Pyramid of Cheops are so advanced that only an extraterrestrial intelligence could have built it; and that the engraved stones of Palenque in Mexico depict an ancient astronaut at the controls of a space rocket.