Isaac is a Watcher, his duty is to decide whether a subject is destined for Heaven or Hell. But having seen the acts that mankind commit against one another, and being refused a chance to help, Isaac chooses to become mortal in an effort to make an example of those who have failed their Day of Judgement. In doing so, Isaac runs the risk of following in the footsteps of those who he has condemned to Hell. Detective Michelle Chase is called to the scene of an unusual killing. A calling card reading FAIL is left behind by the killer. As more victims turn up and with a suspect who is elusive in ways beyond belief, Chase begins to question what she thought she knew.