In the flashback episode, Bobby is revealed as the murderer with Jane hiding his secret. The character had not been part of the official list of suspects, but Treadwell-Collins warned that any character could be the killer. He confirmed that another character was originally the killer, while he had considered making Jane and Cindy the murderers. Story producer Alex Lamb then suggested making Bobby the murderer during a discussion with Treadwell-Collins, series producer Sharon Batten and script producer Manpreet Dosanjh after a story conference. They chose a family member as a culprit because they wanted to relate the story to the show's original premise: a "kitchen sink drama" focusing on family. Treadwell-Collins explained that he wanted the story to be "emotional and come from the heart". The story team intertwined Bobby's recast with the story. Treadwell-Collins commented, "If you look at the pieces now, Jane took Bobby away! We cleverly, I hope, seeded everything." Bobby's attack on Lucy was not filmed, which the executive producer said was a "conscious decision" because he thought it would be "too much" for a child actor.