Extreme temperatures force the Blacklighters to attempt potentially dangerous mining at night. Disaster strikes the Young Guns when thousands of dollars worth of opal goes missing.
The Geran gang are running out of time and push their gear to the limit. In Queensland storms threaten to scuttle efforts to find opal and a mystery illness strikes Les.
The Young Guns tackle their new mine with the lack of air causeing a headache. Pete and Sam have one last chance to find opal to keep their operation alive.
Tensions escalate for new team the Opal Whisperers and an incident for the tunnel rats causes one member to down tools and take a crash course in opal cutting.