Kat Moon will fly into a huge rage on EastEnders in the New Year when she finally discovers the shocking truth about her long-lost son.
The popular character's return storyline will see her life change forever, as she learns that she has a grown-up child she knew nothing about.
June Whitfield's character Sister Ruth will reveal the shocking truth to Kat in early January, gently explaining that her daughter Zoe was actually a twin.
Kat had a difficult labour in a convent in 1984 and only remembers the arrival of Zoe, as viewers found out when Sister Ruth was first introduced in May.
Although shocked and curious by the bombshell revelation, Kat's mood later turns to fury when she begins to suspect that her grandmother Mo Harris (Laila Morse) played a significant role in the cover-up.
Whether Kat's theory is right or wrong remains to be seen, but she'll be back to her classic Slater best as she unleashes her wrath on Mo in scenes which kick off 2016 with a bang.
Amid the ferocious rows and recriminations, the Slaters are also soon hit by fresh tragedy when Kat's father Charlie dies of a sudden heart attack shortly after returning to the Square.
It's clear that the pressures of the family drama have taken their toll, but could Charlie have known something about Kat's secret child too?
EastEnders airs these scenes in early January on BBC One.