Last night (19 February), the murderer was unveiled as Lucy's 11-year-old half-brother Bobby Beale and the surprise revelation left some viewers disappointed.
But while many expressed their annoyance at Bobby being the killer on Twitter, it seems a handful have gone a little further....
Earlier today, it was confirmed that TV regulator Ofcom has received four complaints from disgruntled fans. Perhaps a little extreme, no?!
Up until last night, there were 14 suspects in the 'Who Killed Lucy?' storyline, yet Bobby was not one of them.
However, during a gripping flashback episode, Jane Beale discovered Lucy dead on the floor before Bobby emerged, telling her: "Whatever she says, she started it, she made everyone unhappy!"
Bobby was also clutching Lucy's jewellery box in his hand, implying that he had hit her over the head with it.
Meanwhile, while there was some disappointment with this storyline, viewers were delighted to see the return of a blast from the past - Kathy Beale!
Kathy, played by Gillian Taylforth, was thought to be dead following a car accident in 2006, however it appears she is actually alive and kicking...
The character's ex-husband, Phil Mitchell (Steve McFadden), was seen meeting Kathy but warned her to stay away from Albert Square. So Phil has known for almost a decade that she wasn't dead? Cheeky!
Take a lookat Kathy Beale's EastEnders journey and return here, thanks to our friends at Inside Soap!