The Young Guns rethink their black opal hunt when they face impenetrable mine walls. The Blacklighters' ambitious plan is threatened as their generator dies.

The Bushmen discover a hidden shaft by falling straight down into it. The Young Guns are forced to undertake emergency repairs halfway down a mine shaft.

The Bushmen take over their new recruit's mine, but the new claim proves equally treacherous with little sign of opal. Bishop resorts to explosives to move a wall.

The Bishop and Scotty struggle to make safe a wall and end up causing an avalanche. Meanwhile, the Mooka Boys' bobcat is hit with critical failure.

The Misfits put their faith in an ancient bulldozer for the season’s last dig. Meanwhile, infighting stalls efforts to unearth the Opal Whisperers' haul.