Lucy Beale's murderer isn't set to be unveiled until February, to coincide with the show's 30th anniversary celebrations.
But plenty of people have placed bets on who they think the killer is.
And, after producer Dominic Treadwell-Collins hinted that the show would be paying homage to some of its most iconic episodes, a number of armchair detectives have leapt to the same conclusion:
Nick Cotton is the man who killed Lucy.
But why?
Taking to Twitter, one user explained:"£50 says Nick Cotton murdered Lucy Beale.
"Think about it. What happened in the very first episode of #EastEnders?"
For those who aren't in the know, the first ever episode of EastEnders featured the murder of Reg Cox - a murder which (you guessed it!) Dot Branning's son was responsible for.
What better way to pay homage to the iconic soap on its 30th anniversary, eh?
Take a moment to remind yourself of the first ever episode below:
Doof doof, and all that - but is it enough to make Nasty Nick the killer? Especially as the recent clue of the music box seemingly placed Lucy in her own bedroom at the time of her death?
We suppose it's possible - after all, Lucy was found to be using cocaine at the time of her death. And Nick, as many of us know, is a drug dealer.
There's also the fact that Ian Beale (Adam Woodyatt) and John Altman's character have hated each other for years; what better way for Nasty Nick to hurt his arch-nemesis than by killing his beloved daughter?
Cue rumours that Peter Beale is next to be murdered, and we have more reason to suspect that Nick came to Albert Square with a revenge plan.
Intriguing...
Based on all the evidence and theories so far, who do YOU think bumped Lucy Beale off? Let us know via the comments box below now.