The actress's character Chas Dingle will soon start plotting revenge on her partner Carl King (Tom Lister) and his secret lover Eve Jenson (Suzanne Shaw) when she discovers that they are having an affair.
Speaking to We Love Telly, Pargeter confirmed that Chas's attempts to get even will play out on screen over the next two months.
Asked how far Chas will take her scheming, she replied: "As far as Charity will convince her to, with the pay-off at Christmas."
Discussing the pressure of being part of a festive storyline, Pargeter added: "It makes my stomach churn - it's a massive responsibility."
The star also claimed that Chas would outmatch Eve if the pair ever had a catfight, explaining: "She's known for smacking people - and she's a Dingle."
Chas uncovers Carl's betrayal in this week's episodes of the ITV1 soap.
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