New archaeological discoveries reveal secrets hidden deep inside Egypt's greatest and most mysterious pyramids, and using cutting-edge methods, experts investigate how calamities, graverobbers, and the ravages of time affected these ancient marvels. This is a mashup of S07E03 "Secrets of the Black Pyramid" and S01E02 "Dark Secrets of the Pyramid."

Cutting-edge archaeological investigations at the world's greatest lost cities might finally reveal their hidden secrets, and using the latest hi-tech methods, experts try to explain why these once-proud metropolises were suddenly abandoned. This is a mashup of S02E03 "Lost Temples of the Jungle" and S04E09 "Lost City of the Maya."