Roxy recently discovered that her cousin Phil (Steve McFadden) was the guilty party who stole her money on the day of Ronnie's chaotic wedding to Jack.
Forthcoming scenes on the BBC soap will see Roxy try to get even with Phil by plotting to get the cash back from the Albert Square hardman.
In an interview with Soaplife, Simons explained: "[The plan is] to steal back the money he stole from her. Glenda's in on it with Roxy and they plan to rob the club for what's rightfully Roxy's."
Asked whether the pair succeed, the actress replied: "Roxy deserves to! It is her money. She's furious a member of her own family would steal from her, especially as she's not rolling in it anymore."
Roxy and Glenda launch their scheme against Phil early next month.
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