Emmerdale bosses recently announced that they had cast Gaynor Faye in the role of Megan, who is the half-sister of established regular Declan (Jason Merrells).
Blackburn has now promised that Megan will "really stir things up" when she makes her arrival in the village in early 2012.
"She's an incredibly strong and confident woman who won't allow herself to be used by men - or anyone," Blackburn told Inside Soap. "Megan is very competitive as well, and will really keep Declan on his toes.
"She'll have the likes of Charity and Chas rolling around with laughter, but then half an hour later, she'll shaft them! And she'll do it with a smile on her face, saying, 'It's only business, love!'"
Blackburn also hinted that there could be interesting scenes ahead between Megan and Carl King (Tom Lister).
He said: "When it comes to commitment to a fella, Megan would normally run a mile - but when lots of people in the village tell her not to go anywhere near Carl, it's like a red rag to a bull!"
Emmerdale continues tonight at 7pm on ITV1.
> Emmerdale casts Gaynor Faye as new Macey
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