London, 1888. Committed to the Whitechapel Hall Reform School for "incurable delinquency," Adelaide "Dell" Morton is a precocious, defiant misfit. She's also a voracious reader of the sordid, sensationally popular Penny dreadful stories. In a stroke of luck, she's found a kindred spirit in her poised roommate, Pippa. Their obsession is only further fueled by the Jack the Ripper murders blazing a trail of terror throughout London's seediest streets ... right outside Whitechapel Hall's front door. Desperate for adventure, they embark on their own investigation--and discover an ally in Noah, son of the local butcher. The trio's budding spywork soon yields shocking results: Why was straightlaced Whitechapel teacher Miss Kaye escaping the school the night of the latest crime? Could Jack the Ripper be a she? Delving into Miss Kaye's background, Dell is both horrified and thrilled to find that within Miss Kaye's past lies a chapter dark enough to rival any Penny dreadful... Dell's fixation with Miss Kaye reaches dangerous heights while a series of suspicious events leaves Miss Kaye in sole command of Whitechapel Hall. Trapped in their teacher's ever-tightening web of control, the young detectives devise a risky plan to track her. But what ensues may only propel them into secrets, lies, ruthless acts, and betrayals that go back decades--and a confrontation that will irrevocably change the fates of all involved ... if they survive.