The Vanishings - S9E11

How is it possible that entire ancient cultures seemingly vanish without a trace, consistently and constantly over the centuries? Do they die of disease? Do environmental changes force an exodus from their cities and lands? Does civil war rip their societies to shreds? Or...are ancient - and modern! - extraterrestrials abducting entire cultures en masse to perform experiments for unknown purposes? Is earth truly a giant alien laboratory and has been for thousands, or even millions, of years? How much plastic surgery has Linda Molten Howe ACTUALLY had on her face?! Steve and Joey don’t know, but our plucky ancient astronaut theorists sure think they do! Let’s proooooooooooooobe into The Vanishings!