The worst storm in 20 years devastates the New South Wales' mines. New team the Blacklighters are forced to relocate 300km from their original mining town.
Pete and Sam start a risky project that could set them up for opal riches. Plus, Aaron has to mine his way out of debt after borrowing money to buy his late father's house.
The Young Guns spend all of their savings on a hydraulic digger that causes more problems than it solves. Elsewhere, the Blacklighters are dealt a dose of reality.
The Boulder Boys drain floodwater in pursuit of a suspected opal level. Rod Manning is under pressure after using his wife's favourite opal ring as collateral.
The Blacklighters must relocate Opalzilla after their claim runs dry of opal. And, the Cheals hope to hit the jackpot in a bizarre structure, the Z-fault.
Hard ground at the Bushmen's claim causes damage to their digger. Meanwhile, Pete and Sam hunt for better opal dirt as their 'mega wash-plant' shows promise.
The Tunnel Rats struggle working on unfamiliar ground. The Boulder Boys try to keep their jobs with a last-ditch hunt to satisfy their mining partners.