Shirley Carter (Linda Henry) will try to kill rapist son Dean Wicks (Matt Di Angelo) after she catches him attacking his girlfriend Roxy Mitchell (Rita Simons).
Tense scenes to be broadcast over the festive season will see Shirley walk in on Dean just as he’s pinning a screaming Roxy to the bed.
When Roxy flees the scene, Shirley convinces Dean to take a bath in order to get rid of any incriminating evidence. But when Dean is mid soak, Shirley will then be seen trying to drown her son to death.
The shock showdown will provide an echo for viewers who are aware that Shirley also tried to drown her other son Mick back when he was a baby.
Speaking about the macabre nature of the storylines on the BBC1 over the festive season, executive producer Dominic Treadwell-Collins said: “It’s a tradition that dates back to when Den handed Angie those divorce appears.
“Pam St Clement told us that they once tried to have a happy Christmas where everybody hugged and it had the lowest ratings ever.
“So people expect EastEnders to be a bit gruesome. You’re arguing with your family and you’re having a dreadful day, but you can watch EastEnders and say, ‘Well at least I’m not a Beale’ and then feel a bit happier.”
You can watch a 60-second rundown of Christmas and New Year on EastEnders below.
And visit our dedicated EastEnders page for all the latest news, interviews and spoilers