Abandoned towers in southern Greece are the ruins of a fearsome warrior civilization descended from the Spartans, and new discoveries reveal the role these towers played during generations of violent blood feuds among the clans that lived here.

The ruins of a great wall that once marked the edge of the world hold the secrets of the ancient soldiers who stood watch here long ago; new discoveries reveal who the wall was meant to keep out and why the site is littered with skulls. This episode is a mashup of S06E03 "End Times on Lake Michigan" and S05E02 "American Atlantis."