Casey finds himself in hot water in scenes soon to air in Australia as he confesses that he lit a fire at the headquarters of one of the River Boys' rivals.
Shortly before turning himself into the police, Casey has an emotional heart-to-heart with his older brother Brax (Steve Peacocke), who advises him that it's best to come clean.
Younes told TV Week: "There's this moment where Casey breaks down in front of Brax. Casey's the emotional and volatile one but you rarely see him break down, so the fact he does so in front of Brax shows he hasn't meant to do it, he's got himself too deep and now doesn't know what to do. Brax is afraid for him."
Asked how Casey feels when he confesses to the police, the actor replied: "He's afraid, but all the emotions and feelings have gone. He's almost stoic."
Younes also predicted that the prospect of a stint in juvenile detention will have a negative impact on Casey's romance with Ruby Buckton (Rebecca Breeds).
"He starts to push Ruby away for her own good, because he doesn't want to drag her down with him," he explained. "She doesn't understand what she has done wrong, but Casey knows it'll be a strain on her if he goes away."
Home and Away airs these scenes next week in Australia and later this year on Channel 5 in the UK.
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Watch Lincoln chatting about Casey earlier this year in the video below:
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