Chasing a lead, Josh Gates rushes to Poland to join locals opening a secret Nazi tunnel system dug into a dormant volcano; he helps remove the stone wall built by the retreating Germans and enters to see what's been hidden for more than 75 years.

Josh Gates heads to the Wild West in search of the hidden loot heisted by infamous lawmen turned criminals, the Dalton Gang. Re-tracing the Gang's last steps and investigating their final, deadly shoot-out, Josh chases a fortune worth millions today.