This documentary about the Great Sphinx of Giza was originally seen on NBC. Narrated by Charlton Heston, the film searches for answers to questions about this most enduring of mysterious monuments. Who built the Sphinx? How were the 200-ton stone blocks lifted into place? Does the face on Mars, as seen in official NASA photographs, have a connection with the Sphinx? Do the predictions of psychic Edgar Cayce about the Sphinx have validity? The program has been expanded to include recently discovered evidence of rain erosion that suggests that the Sphinx is thousands of years older than was previously thought. This fact gives credence to the idea that the Sphinx was created by a vanished civilization, long before the time of the Egyptians.