One year after Ryan Hardy's pursuit of serial killer Joe Carroll, a healthy and healed Ryan is living in New York City. On the surface, it appears Ryan's gotten his life back together. But deep down, his obsession with Joe continues to grow. Then, on the anniversary of Joe's death, a new murderous rampage leaves everyone shocked and determined to discover the truth.

Ryan continues his search to find the correlation between the recent tragedies in New York City and Emma and the existing members of the Havenport cult, while the FBI becomes increasingly aware of his undercover agenda. Meanwhile, a shocking event leads Joe to put a new plan in action.

After the latest shocking revelation in the case, Ryan and Max attempt to put the pieces together and stay two-steps ahead of the FBI, despite Weston's constant warnings to stay out of the way. Meanwhile, Emma becomes even closer to Mark and Luke, while Joe and Mandy meet up with a follower in search of assistance.

In an attempt to learn new information, Ryan and Max capture a suspect. But complications lead to a game of dangerous cat and mouse. Also, Joe grows accustomed to his surroundings and establishes a plan of his own, while Emma realizes she is in dangerous company.

Looking for back-up and hoping to execute their plan, Ryan and Max contact the FBI. But Weston has other ideas, leading to a standoff between good and evil. Meanwhile, Joe's new relationship escalates into uncharted territory, and Luke finds himself in a troubling situation.

Ryan and the FBI continue their hunt for Lily Gray, and are forced to redirect their search when a new threat enters Max's life. Meanwhile, Joe, Emma and Mandy arrive at their latest hideout, but quickly realize things aren't what they seem.

With Joe Carroll awaiting execution on death row and all signs of his following erased, Ryan Hardy has moved on from the dark events of his past. But his newfound happiness is shattered when a series of brutally staged tableaus threatens to tear open old wounds. Ryan and his team are forced to unravel a twisted web of violence before it destroys them all - leading them to face a terrifying truth: Joe Carroll was just the beginning.

Ryan believes he has found the connection between Andrew and Mark, but he and the FBI are still unsure if - and how - Joe Carroll might be connected. Meanwhile, tension between Mark, Kyle and Daisy mounts and Ryan soon finds himself in a dangerous situation, in which facing the truth is the only thing that will set him free.

With their latest target on the run, Ryan and Mike follow a tip to a small town to investigate and confirm he isn't seeking protection. While in town, they both discover an even larger threat who has managed to avoid suspicion up until now. Meanwhile, Max struggles to make a confession.

After the latest shocking discovery, Ryan finds himself being tracked by the new illusive killer and a game of cat-and-mouse begins leading them both back to Joe Carroll, for different reasons. Meanwhile, Max and Mike look for a stolen clue and Mark makes a shocking decision.

The FBI hunt for Theo continues and the stakes are higher than ever as some of their own come under attack.

As suspicions rise alliances are shaken and no one is safe in the harrowing final heart-stopping moments.