Fans of the show will see Peggy back in Walford for one episode as she makes a visit to Albert Square during the special week of live shows.
Peggy will return to her former home of The Queen Vic, where she'll come face-to-face with the new landlord Mick Carter (played by Danny Dyer)! The episode will air on Tuesday 17 February.
Speaking about working with Barbara, Danny said: "It was a real moment when I got told because for me, I think EastEnders had some of its best moments when Barbara was at the helm. So It was a shame that when I came in, Barbara was no longer in the show."
Danny, who has previously revealed his nerves ahead of the live shows, added: "I've known Barbara for a little while but not well. But she was lovely. She wound me up and said, 'Oi you, I want a word with you!'
"I was like, 'Oh no here we go' and then she wound me up and gave me a big cuddle. She gave me the thumbs up which is a massive thing!"
EastEnders' highly-anticipated live anniversary week will air from Monday 16 until Friday 20 February on BBC One.
It's set to be an "explosive week of drama, special shows and a flashback episode" with shocking revelations and twists as Lucy Beale's killer will finally be revealed.
There will be a series of live elements in all episodes that week and a fully live half hour episode on Friday night at 8pm.
Meanwhile, EastEnders bosses have given fans the opportunity to go back in time and watch the very first episode of the soap from 1985, which will be available on BBC iPlayer and the Red Button from Monday 16 February.
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