Secret Tunnel Warfare Preview
Preview: Season 43 Episode 1 | 30s
During World War I, the Allies and Germans repeatedly struggled to break the hideous stalemate of trench warfare. In the winter of 1916, Allied engineers devised a massive surprise attack: over 1 million pounds of explosives hidden in secret tunnels driven under German lines. Building the tunnels was desperate work, with tunnelers at constant risk from flooding, cave-ins, and enemy digging teams.