When Nathan and Audrey find another dead body with a bolt gun incision, they worry that Tommy may have survived their last run in and is still killing people. The truth, however, is much more sinister. The dead body IS Tommy's. He was actually killed when he first got to Haven, meaning that someone must have taken his place.
Across town, the florist van that The Guard uses to transport troubled people into Haven is found abandoned, except for Ginger Danvers, a 7 year-old-girl who is traumatized that her father left her alone. Nathan investigates the incident by going to visit his girlfriend Jordan, who is part of The Guard, but she claims to have no knowledge of who was being transported or why. It turns out that Jordan is lying and hiding Lance, the van driver, in the back of her diner.
Back at the Haven PD, Ginger shuts down on Audrey and Claire but Duke, with his charismatic ways, is able to break through to her. The two of them form an instant bond and Duke, rather irresponsibly, takes her out of the police station to go get ice cream. When Ginger vanishes, he calls Audrey and Nathan to help but it turns out it was Lance who took her.
Lance tries to deliver the girl to Jordan but Ginger escapes and Lance kills himself on the spot while Jordan gives chase. The fact that Lance killed himself because of something Ginger said indicates that she, in fact, is the troubled one, and her trouble is making people do whatever she asks. Once free, Ginger finds Duke again and unwittingly forces him to play with her in a dangerous way that ends up hurting him.
Later, Audrey helps Ginger understand her power and Ginger, in turn, tells them that Jordan was a part of her attempted kidnapping. When Nathan confronts Jordan, she sends him on a wild goose chance and tries to kidnap Ginger again. Nathan and Audrey then use Ginger's power to get the truth out of Jordan: The Guard wanted Ginger so they use her to control Nathan. They thought that if they could control Nathan, then they could force Audrey to go into the barn. This is important because the Guard knows that if Audrey goes in the barn the troubles will disappear completely for 27 years.
Soon, Nathan and Audrey raid the safe house where The Guard is holding Ginger's father and rescue him. As soon as Ginger is reunited with her father, her trouble vanishes so she can't help when The Guard gets the drop on them. Nathan offers to let Jordan out of jail in order to keep Ginger and her father safe.
Crisis averted, Audrey turns her attention back to the Bolt Gun Killer and tracks him down to a tuna cannery across town. What they find there is remarkable—the Bolt Gun Killer is a "skin walker" who can masquerade as anyone he or she skins. And, even worse, they find Tommy's skin intact which means the killer is now pretending to be someone else, but who?
Colin Ferguson gives his final thoughts on the season finale of Haven.
In Haven's fourth season finale, William's plan to turn Audrey back into her original self, collides with Audrey, Duke and Nathan's plan to trap William back in the dark place he came from.
Get a look at the references to Stephen King's works from the season 4 finale.