"Who Killed Lucy Beale?" is a storyline from the BBC soap opera, EastEnders. It was announced on 21 February 2014 and began on 18 April 2014, when Lucy Beale (Hetti Bywater) was discovered dead on Walford Common from a deliberately inflicted head injury. The storyline reached a peak during EastEnders Live Week on 19 February 2015, the show's 30th anniversary episode, during which Lucy's brother Bobby Beale (Eliot Carrington) is revealed to have killed her following a confrontation at home. Bobby's adoptive mother, Jane Beale (Laurie Brett), had covered for him, moving Lucy's body to Walford Common and convincing Bobby that he was not responsible for his sister's death. The storyline was revived in July 2015, where it showed how the Beales coped with covering the secret and many locals being wrongfully arrested for committing the crime. The storyline reached another peak in December 2015, when Bobby discovers the truth. The storyline was revisited again in May 2016, when Bobby brutally attacks Jane, and reveals in a busy pub that he killed her and Lucy. However, Jane survives the attack, although facing potential paralysis, and Bobby is arrested and charged. The storyline ends in the 16 June 2016 episode when Bobby is sentenced to three years in custody for killing Lucy and causing grievous bodily harm upon Jane.
The murder story is in the style of a "whodunit" mystery. Only four members of the show's production team knew who was responsible for Lucy's death. The marketing campaign for the storyline is EastEnders biggest yet; the first specially created trailer aired immediately after the murder. The identity of Lucy's killer was shown in a special live episode marking the 30th anniversary of EastEnders in February 2015. The story, which began on Good Friday 2014, is described by executive producer Dominic Treadwell-Collins as being "emotionally right, true and very exciting" and that, after initially deciding on a killer, they came up with an alternative killer early in the planning stages as their initial choice "didn't come from the heart".