Margery was a very famous medium from Boston who had fooled many people and many experts into believing that she had genuine powers as a medium. A team of psychical investigators decided to conduct investigations into her supernatural powers. Many of the investigators would be seduced by Margery and end up working for her as confederates covering her deceptions. In this expose, Houdini recounts their battle of wits and cunning as he investigated her claims as he eventually discovers her secrets and exposes her.