Secrets of the Underground
A search for an underground escape route said to have been used by Al Capone. Also: who or what built earthen mounds in Washington state.
3. America's Buried Massacre
0.0Feb 28, 2017 · 60 min
Rob Nelson hunts for a legendary mass grave that could expose a dark secret of America's industrial past. High in the mountains, a giant lake is mysteriously disappearing, and Rob uses cutting-edge technology to find out why.