As already announced, Kat and Alfie (Jessie Wallace and Shane Richie) will be making a brief return to Walford this Christmas, but they'll be joined by another blast from the past.
Derek will reprise his role as Kat's father Charlie for a guest appearance in the new year - but bosses are keeping tight lipped as to why he's returned!
It's set to be a dramatic return, however, as Kat and her father have always had a turbulent relationship. Will this be a happy family reunion for them all? Or will Charlie and Kat's reunion stir up more ghosts from the past? Viewers have already been let in on the secret that Kat has another son that she has no idea about.
Speaking about his return, Derek said: "I'm so excited to be coming back into such a big and important storyline and I can't wait to get stuck in and be back with the family again."
Charlie was last seen in Albert Square in December 2013 when he came to spend the festive season with Kat and Alfie for their final Christmas in The Queen Vic.
While his storyline is being kept top secret, we do know that his return sets the scene for Kat and Alfie's new spin-off drama, which will see them head off to Ireland to search for answers to some very big questions.
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