Lucas has previously overcome a gambling addiction, but slips back into his old ways as he struggles with debt problems.
The latest crisis for Lucas leads to him agreeing to play poker with bad boy Robbo Slade (Aaron Jakubenko).
Scott Major, who recently filmed his final scenes as Lucas, told TV Week: "He's under a heap of financial pressure. He's put a deposit on a new apartment, the Ramsay Street house hasn't sold and there's another baby on the way.
"When Lucas comes into some money, he's tempted by Robbo to join a high-stakes poker game."
Lucas receives a confidence boost when he wins his first game, but when his pregnant fiancée Vanessa Villante (Alin Sumarwata) suffers a health scare, he decides that he needs more money to pay for private medical treatment.
Unfortunately, this time Robbo decides to fix the game, setting Lucas up for a huge fall.
Major added: "Lucas has no hope of winning thanks to the fixed game Robbo is playing, and he ends up in debt."
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