Emma’s passionate about her work and has a strong moral code. She's no maverick but she's instinctive, ambitious
and has a keen ability to read, understand and relate to people – all of which have helped her rise through the ranks quickly to become a Family Liaison Officer (FLO).
Emma's dealt with murder cases before in the past but never a young girl's murder. She knows from the first visit that it's not going to be a walk in the park but if they manage to bring Lucy’s killer to justice it's potentially a game-changer for her career…she died on January 2, following a car accident.
Summerhayes is a police officer tasked with finding the killer of murdered character Lucy Beale. Of her casting, a show insider said: “Anna has a huge role to play in one of the biggest soap storylines for years. She is the one who hopes to be able to pinpoint the killer and to begin with there are plenty of suspects.” Of the police officers investigating Lucy's death, series producer Dominic Treadwell-Collins had previously said: "We don't want the police to come across as incompetent soap police. If the police were really good, we'd have no story to tell and there'd be nothing to watch, but as time goes on, some of the police are changed and some people are taken off the case. We also try to characterise each police officer, so they're not just generic fact-givers. They're all characters in their own right and they've got loads of stories running through as well."
Summerhayes first arrives in Walford with her colleague, DS Bryant, and together they reveal to a shaken Ian Beale that his daughter, Lucy, is dead. She reveals that she will be acting as his Family Liaison Officer and later accompanies Ian to the mortuary so he can view Lucy's body. Summerhayes returns the following day with DCI Irving and explains that forensics will need to examine Lucy's bedroom. She speaks to Lucy's twin brother, Peter, asking whether Lucy had any enemies. Peter says that Lucy had no enemies, but he then believes that Summerhayes is hiding information from the family. Summerhayes later visits the Brannings, and questions Lauren Branning about Lucy's final movements and her relationships with local residents.
The following week, Summerhayes arrives at the Beales and reveals to Ian, Peter and Ian's fiancée Denise Fox that Lucy was in fact murdered, not involved in a tragic mugging as had first been thought. She also reveals that before her death, Lucy had been having an affair with an unknown man, and that they need to find out who she was seeing. Lauren later tries to contact Summerhayes when she believes that Jake Stone was Lucy's murderer, but Summerhayes fails to get back to her. When Jake is later arrested, Summerhayes assists in questioning him and later visits the Beales to tell them they are currently building a case against Jake and he will not be granted bail. After a heart to heart with Max, the two give into their feelings and kiss. This leads to them sleeping together. Emma confronts Max about what happened the next day but after they sleep together for the second time, beginning an affair. She died on the 2nd of January 2015