As opal and water dry up, Slim Pickings' efforts to recycle precious dam water and mine their claim are derailed by a slipped excavator track and busted wash plant motor belt. The Blacklighters face off against big rain and even bigger egos as they desperately scrounge for any last opal in the barren walls of their exhausted Land of Promise claim. Facing impenetrable rock at the Lunatic Claim, the Mooka Boys are forced to enlist an explosives expert -- blasting their mine sky high and pushing the team deeper into debt on the hunt for elusive Andamooka black opal.