Katie McGuire is hired by her former mentor, architect Paul Richter, to research the history of the 480 building for an "anonymous" client. While exploring the historic building, Katie and her friend, Billie Jo, find an old red-leather diary hidden under the floorboards on the second floor. Apparently written by Sadie Nolan (considered to be a woman of ill repute), the diary from 1928 comes alive in the form of an unlikely romance. Through this romance, Sadie dares to live the life of which she's always dreamed. Meanwhile, Dr. Clifford Westbrook and his partner, Dr. Jonathan Blake, create something so evil that they now have to choose between their success and their secrets. Burlington, Wisconsin may not be the sleepy little town everyone believes it to be.