In the back of her mind

Kathryn Blanche Ellis was born 24 years ago in London, specifically in Westminster on the 6th of January at exactly 03:33 AM in the year 1901.

Now you're probably thinking; growing up and being a young adult in 1920's London, the age of flappers and jazz, must have been glamorous and prosperous right?

Well it was anything but that for aspiring female detective Kathryn.
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After her parents were killed by the notorious serial killer "The Director", who's name is derived from their gruesome habit of posing their victims after their brutal murders, six year old Kathryn is left an orphan and sent to "The Asylum", a place dedicated to female orphans.
Yet, despite her parents' death adding to The Director's already long list of 23 victims, the police continue to do nothing, due to all the victims being working class and therefore considered 'slum urchins'. Discovering this, an enraged but guilt-ridden Kathryn devotes her entire childhood and youth to learning the law and searching for The Director, in hopes of being able to put an end to the dastardly killer herself.

Amongst the people and things that aid in Kathryn's journey towards her goal, the most valuable thing to her is the mysterious voice in the back of her mind she's had since being a young girl, that seems to only sound whenever an individual lies to her, who she firmly believes is The Director's victims assisting her.
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When The Director's latest victim is Lord Barrington, a high-class member of the House of Lords and the 34th victim, Westminster's detectives finally begin to take matters seriously and look into the murder, and in spite of being against working with a woman, enlist the help of Kathryn - who is perfectly knowledgeable in the murder cases of The Director and who is dead set on making sure the other victims' murders are avenged as well, including her parents.

Will Kathryn find The Director and put a stop to his brutal killings or will she become his next victim and 'model'?