The Twins, Book 1 — R.G. Miller

Inseparable twin sisters Stacey and Jannifer McHill were known for their beauty and charm, but behind their innocent facade lies a twisted secret. When a series of brutal murders begins to plague Upper Manhattan, the twin's true nature is revealed. Driven by a shared need for revenge, Stacey and Jannifer McHill embark on a twisted killing spree that will shock the citizens of New York City. Detective Iris Williams is assigned to the case, a case that will challenge her sanity. Will Detective Williams stop the murderous twins before the city explodes in an all-out panic?