Ep 17. School of Hard Rocks

With Rod away on urgent Mines Department business, leaving Les in charge, Sam and Ben battle a dangerously steep ramp underground. After sinking a new shaft to save their backs, The Bushmen are stonewalled by impenetrable rock. It's the last dig of the season and Dan and Renee are fighting ultrahard rock in a hail Mary search for opal at Benito's, until dust and gusts force the pair to return at night where they encounter thieving 'night-shifters'. After a season-long battle against an unyielding rock cap, The Mooka Boys are finally ready to start tunnelling toward black opal glory, until their last working machine suffers a catastrophic breakdown.