Vulnerable Casey, who is set to go to prison for shooting his evil dad, is knocked unconscious by a man named Kyle who has been spying on him for weeks.
Lincoln Younes, who plays Casey, told TV Week: "Casey's knocked out and comes in and he's in the outback and doesn't know what has happened to him or how long he's been there.
"There has certainly been someone watching him for a few weeks, which you've seen snippets of, and the inference is that it's related to his dad."
Younes further teased: "There is a big reveal. It's a shocking revelation and Casey is obviously confused when the revelation comes out.
"He is slowly realising the repercussions of shooting his dad have extended further than he first thought. I think Casey is realising there are bigger consequences to what he's done - one's he couldn't have predicted."
When Casey disappears, Brax assumes that he has run away to avoid his court appearance.
Since killing his dad, Casey's mental state has deteriorated, with the River Boy nearly drowning in a surfing accident last week.