The Bushmen, Rod Manning and Les Walsh, along with new recruit Sam Mehan, put their lives on the line in the most dangerous mine they have ever worked -- battling subterranean waters and a deadly crumbling roof. Gross incompetence with a new bulldozer lands The Blacklighters in hot water with Mark's wife ahead of a treacherous Opalzilla move to a new claim, sinking the team deeper into debt at season start. The Cheals' new million-dollar partnership with Grawin local Mark Bressan faces a trial by fire as incompatible machinery and equipment failure brings their first dig of an ambitious season to a grinding halt.