The actress is joining the ITV soap as Eva Price, alongside Michelle Collins as Rovers Return manager Stella Price and John Michie as Stella's boyfriend Karl Munro.
"My first scenes were in the Rovers and I just had to take a few minutes and say to myself, I am in the Rovers Return and I did have a bit of a mini freak out!" she told What's On TV.
"It's amazing. The show is just absolutely legendary. It's a brilliant thing to be a part of and I am honoured and thrilled to be a part of it."
Tyldesley hinted that her alter ego Eva will bring excitement to the Street, adding: "[She will bring] trouble. She gets bored with people quite easily. She has always dated older guys because she finds them more interesting."
She went on to say: "Eva is high maintenance. She likes to keep up with the latest trends. She's very spoiled. She expects her mum to keep her in the best wardrobe. She is very on trend and wears the latest fashions. She does look up to the WAGs."
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