The one-time Walford witch joins the cast of Poirot (ITV1, Weds, October 27) for a Halloween themed episode…

What can you tell us about your role in this brand new Poirot?
“It was filmed so long ago I can hardly remember! But I do recall that I play Mrs Reynolds, who is the step-mother of the murder victim and the episode opens with a spooky Halloween party, full of kids dressed as witches and pumpkins!”

Did you enjoy working with David Suchet?
“Yes, very much. And Zoe Wannamaker is back in the episode as Ariadne too. They are people I have watched and admired for years so working with them was a blessing. David is still so passionate about the role, it’s infectious.”

People remember you for lots of roles, but we have to ask you about your EastEnders character – evil Stella!
“I loved Stella. I look back at that time fondly. It’s something I never thought I’d get the chance to do, be in a soap. Working with Barbara Windsor and Steve McFadden – they’re legends in their own lifetimes aren’t they?”

Did you get any abuse on the street during your EastEnders days?
“None. The producers took me to one side and were very worried about people spitting at me; they told me I must tell them if anything happens. They were more worried than I was! But on the whole people were lovely to me. I’d get some funny looks from kids, but nothing nasty. It’s just pretend isn’t it?”

You are due to appear in the new Harry Potter film – did you film any scenes with your sister Emma [Thompson, who plays Madame Trewlany]?
“No, that would’ve been fun wouldn’t it? Our roles never crossed over because all my scenes are at the Ministry of Magic. I play Mafalda Hopkirk, who Hermione drinks Polyjuice to pretend to be. So, in essence, I am playing Emma Watson’s rather flamboyant costume. It was great being part of it, right at the end.”