Speaking to MSN, she also praised returning Albert Square co-star Letitia Dean, having only recently met her for the first time.
"I was grateful to have another fantastic woman to work with," Joyner said. "We've been doing quite a lot of stuff, so it's lovely. They start off a bit feisty, but they're going to get on quite well.
"Sharon's such a beautiful, iconic character and she puts everyone's heckles up. You can see Kat's not impressed and Tanya's not too sure. It's a powerful week and it's going to be interesting."
Speaking about helping Dean to settle back in, she commented: "She's been in Albert Square forever hasn't she? I've never met Letitia before and I've only just started working with her, so I just assumed that she'd know far more than me about everything."
Joyner went on to divulge about her own character: "She makes a new friendship with Sharon and there's going to be more involving Cora. And, of course, Tanya is engaged so will there be a wedding?"
Letitia Dean makes her highly-anticipated Walford return on Monday, August 13 in a dramatic episode which sees Sharon visit Phil as her son is abducted on her wedding day.
> EastEnders Steve McFadden teases Sharon "roller coaster" return
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