After being chased through the halls of an elite hotel by a killer, aspiring architect Neddy Suidek must cope with post traumatic stress. As she tries to move on and land a dream position working for Daniel Burnham, the architect masterminding the World's Fair in Chicago, she becomes the focus of con-artist and serial killer H.H. Holmes, who hires her to design the third floor of his building. Torn between two worlds, Neddy realizes that if she works for the upstanding Burnham, she can only be a secretary, but if she throws herself into the snake pit of Holmes' murderous ways, she can live her dream of being an architect. The Fair and the Castle is The Gilded Age meets Jack the Ripper.