It was the biggest whodunnit of 2015, with Hollyoaks fans stunned to learn that the Gloved Hand Killer was, in fact, Lindsey Butterfield.
But, despite viewers being well aware of Lindsey’s murderous streak, she has yet to be caught.
And, terrifyingly, she (and her hypodermic full of horrors!) is still at large.
However it seems as if her days are well and truly numbered, despite the fact that her sister Kim (Daisy Wood-Davis) has been arrested for Lindsey’s crimes.
In upcoming scenes, Hollyoaks viewers will watch as Esther Bloom (Jazmine Franks) visits Kim in prison.
The young nurse-turned-jailbird has just one request for Esther; to spend some time with her twin sister, Kath (Mikaela Newton), who is living at a care home where she receives round-the-clock care.
Kind-hearted Esther does just that, spending time with Kath, reading to her, and even going through old family photographs together.
But when Esther shows Kath a photo of Lindsey (Sophie Austin) as a child, things suddenly become a lot more sinister.
Kath, visibly frightened and disturbed by the photograph, flinches away - leaving Esther puzzled over her unusual reaction.
What Esther has yet to discover, however, is that Kath has a very good reason to be afraid of her older sister.
As soap viewers saw in special flashback scenes during Hollyoaks' 20th anniversary week, Lindsey was incredibly jealous of the bond twins Kim and Kath shared.
So, in a bid to feel closer to Kim, she purposefully shoved Kath into a lake.
The incident (which was intended to kill Kath) left the youngster with severe brain damage, meaning that she cannot move or speak.
Lindsey later told Kim: "She caused the problems, she caused the fights. I only needed one sister. I only needed you.
"She was never your twin, never really. Life didn't make sense. I took control for you."
Will Esther put two and two together and realise that Kath’s fearful reaction to her sister is evidence of Lindsey’s sinister side?
After all, Kath was the trigger to Lindsey’s serial killer instinct; it seems only fitting that she should put an end to it, too.
Hollyoaks airs these scenes on Tuesday, March 22 and Wednesday, March 23 at 6.30pm on Channel 4.