Show bosses have today (September 30) revealed more information on the guest character, who is the cousin of Georgia Brooks (Saskia Hampele) and Toadie Rebecchi (Ryan Moloney).
Gemma is being billed as a schemer who will "rock Erinsborough to its core" as she settles into the area.
Moving into Ramsay Street, Gemma seems obsessed with Georgia and sets out to divide and conquer anyone who is close to her - including Georgia's boyfriend Kyle Canning (Christopher Milligan) and best friend Kate (Ashleigh Brewer).
Kathryn Beck, who plays Gemma, commented: "I loved playing Gem because she pushes all the boundaries and just when you think she has gone too far, she goes further."
Beck's previous credits include roles in Home and Away, Puberty Blues and All Saints.
Neighbours airs Gemma's arrival on October 7 in Australia and November 4 in the UK.
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