Eastenders star Shane Richie has spoke about the reveal of Kat's secret lover, saying that it will surprise fans.
Viewers will finally discover which of the three Branning brothers is Kat's mystery man on December 20 when Richie's character Alfie confronts his unfaithful wife over her lies.
Alfie takes action when he suspects that Kat (Jessice Wallace) is still having her affair, following her to her secret bedsit to demand answers.
When asked by the Radio Times if the plot conclusion is surprising, Richie said: "Oh, big time. And it's really interesting about how we play the Branning card as to which one of them it is.
"The way it's worded, you believe it's one brother in particular and then that all changes and you go, 'Oh, it's him!' Because we make people believe it's another Branning - the way it's worded, the way I face up to one of them.
"The audience will all think it's one person in particular, but then I throw a curve ball and it all kicks off. It's great."
Richie added that he doesn't think Alfie can forgive Kat for her betrayal this time, saying: "He's done with the lying. In the past, Alfie has forgiven Kat, but this time I really do not think he's going to forgive her."