Despite leaving Albert Square for a new life in Spain after winning the lottery, the family make a brief return to see Kat's cousin Stacey Branning. However, things aren't all that they seem and drama is not far behind...
Before they left, there were many secrets answered. We found out that Kat has another son she doesn't even know exists, and Alfie has a brain tumour, which he is keeping from his wife.
However, the secrets will explode as Kat and Alfie return home to Walford, which will then set the scene for their new spin-off drama, which will see the couple head off to Ireland.
Speaking of their return, Shane said: "I'm really excited to be heading back to EastEnders with Jessie this Christmas. It's wonderful to be back in Walford and to be playing out several big twists to Kat and Alfie's story that will set the scene for their new life in Ireland."
Jessie added: "I can't wait to start filming these episodes. The drama that Kat and Alfie have in store when they return to Walford is huge and although secrets will be revealed, more questions will be raised leading them to head off to Ireland in search of answers..."
Executive producer Dominic Treadwell-Collins teased: "Christmas in Walford is always the perfect time for uncomfortable family reunions – and Kat and Alfie's brief return will lead tears, laughter… and a mountain of secrets being unearthed for the Slater family. As Kat and Alfie hold on to each other and their marriage, the discovery that Kat has a secret son will lead to seismic waves through the Slaters – and ultimately lead to the Moons realising that the answers to so many questions lie across the sea in Ireland."
Kat and Alfie's spin-off drama will be six hour-long episodes and is due to transmit in 2016. The name of their spin-off drama is still to be announced.
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