Genesis 'Gennie' Walker, played by soap newcomer Sian Reese-Williams, arrives in the Dales on Tuesday, April 1, much to the shock of her estranged father Shadrach (Andy Devine) and her biological sister, Chastity (Lucy Pargeter).
Gennie's planned meeting with her father – who gave her up for adoption – is scuppered by a shock road accident, leaving her fighting for her life in hospital.
Of her new role, the 26-year-old said: "I'm thrilled to have been given this fantastic opportunity. Emmerdale is such an iconic programme and I can't wait to take my place in the Dingle family."
The soap's new series producer Anita Turner added: "I'm delighted to welcome Sian to the show and we've got some exciting storylines planned.
"Chas, for one, is left reeling from the news that she has a long-lost sister. Genesis is not your typical Dingle and she's in for a real culture shock when she meets her biological family."
Reese-Williams – who has worked on theatre productions of As You Like It, Be My Baby and The Dreaming – begins filming with the Yorkshire soap this week.