When the man who abducted Audrey makes a critical mistake by attacking a woman in front of an ATM camera, he creates the first break in the case: The ATM's camera captures the man's tattooed arm. As it turns out, the tattoo the killer bears is the same tattoo that Nathan wears.
Even though he only got the tattoo so that he could kill Duke if he had to, Nathan now needs to find out what the tattoo really means. Luckily, Vince and Dave need information too. After a bit of a standoff, Vince and Dave tell Nathan the name of a café where he can find more information about the tattoo wearers. Nathan, however, is reluctant to tell them as much as he used to. Later, Nathan pursues the lead and ends up finding a beautiful woman at the diner who is distrustful at first but seems to be taken in by Nathan once they talk further.
Since Nathan is out of pocket, Tommy steps up as one of Haven's new detectives. Like Nathan, however, he is unwilling to talk to Vince and Dave. Feeling too cut out of the loop, Vince and Dave decide to delve into Tommy's past and uncover some secrets, but when they confront Tommy they find out that Tommy has done his homework on them too. The three of them reach a chilly understanding that they should leave each other alone.
Across town, Audrey and Nathan catch a new case involving a swim instructor being eaten by a shark even though she was only in a swimming pool. Later, another incident occurs when a man driving down the street is suddenly inundated with water and fish. As Audrey and Nathan try to solve the case, Duke is determined to follow along, seemingly to annoy Nathan.
When two more people have unexplainable experiences with water in town, Audrey knows for certain that it's a "trouble" but whose is it? Retracing their steps, Audrey Duke and Nathan all find themselves at the home of the man whose car was flooded by seawater. With his dying breath, he admits that he just ran a woman off of Cliff Road.
Audrey quickly deduces that the woman who is trapped at the bottom of the cliff is the one with the "trouble" and it's her frightened thoughts that are causing everyone she thinks about to share her predicament. They race to Cliff Road and find her car. Before they can stop him, Duke lowers himself down the cliff and uses the woman's blood to power up.
Nathan pulls his gun, certain that Duke is about to kill the helpless woman but Audrey stops him. It's a good thing she does, since Duke is only using his superhuman strength to free the woman from her car...and prove to Audrey that he does not have to follow the legacy of his father.
Meanwhile, Dr. Callahan and Audrey explore Audrey's past lives and, remarkably, Audrey begins to remember her life as Lucy. And, in his lair, the killer has started assembling his "trophies" into a macabre sculpture, of sorts.
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.