Once I Had a Love (S01E01)

Karen Miller, now living under the alias Emma Hall in witness protection, forms a friendship with a local girl. Tragically, the girl’s sudden death unleashes haunting memories of her former lover, Kit Parker, a serial killer. Emma becomes increasingly anxious that she may have played a part beyond merely providing him with an alibi. Meanwhile, Mary Barlow, mother to one of Kit's victims, is determined to track down Karen, employing a predator to ensure that the woman who evaded justice is finally held accountable for her past.