Audrey remains in Haven to investigate her mother's connection to the Colorado Kid, but ends up working with Nathan to determine the cause of a mysterious series of incidents that involve butterflies and otherworldly phenomena centered on a angry reverend, his passive daughter, and her foster son.

Audrey is the only one who realizes that there are Christmas decorations in July that no one else finds unusual. The out-of-season decorations are only a prelude to the bizarre bisection of a surfer and a series of escalating disappearances of people who no one can remember except Audrey.

Haven is beset by biblical plagues. Duke continues looking for information on the tattoo, with a little help from his past. Audrey and Nathan check out Audrey II, and try to figure out what to do about Chief Wuornos.

FBI agent Audrey Parker travels to the town of Haven to investigate the death of an escaped prisoner who fled to his hometown. She soon discovers the man's death is merely the tip of a very large iceberg of supernatural phenomena.

A plague of insanity strikes at a local hospital, causing the doctors to go insane... and the patients to become normal. Audrey and Nathan seek to discover the cause before it spreads further.

Haven is stricken by a mysterious plague when animals and plants alike are destroyed by exposure to hydrochloric acid with no discernible source.

A series of fatal animal attacks lead Audrey and Nathan to investigate a local woman who supports animal rights. However, they soon discover that while she may not be Troubled, the person responsible is... and Chief Wournos is the next target.

A single day keeps repeating for Audrey, who finds a deadly accident linked to the phenomenon.

Young men in Haven start aging at an accelerated rate, and Audrey and Nathan attempt to find the source.

Audrey and Nathan take a search party into the woods to find a missing boy whose disappearance may be connected to the Troubles, and receive some unwanted help from Driscoll.

With Nathan's help, Audrey finally locates Lucy Ripley and goes to confront her. Meanwhile, Duke and Dwight join forces to discover what Duke's father Simon left for his son.

Nathan makes a desperate play to protect Mara from the furious citizens of Haven, leaving Dwight and Duke to deal with a deadly trouble that threatens to burn the town to the ground.

Dwight and Charlotte work to clear Nathan's name when the citizens of Haven put the lawman on trial. Hoping to buy them time, the brothers Teagues moderate the courtroom proceedings, while Audrey continues her quest to solve the darkness troubles.

A banker hides a dark secret that connects him to a killer hiding in Haven. Meanwhile, Duke helps a young runaway and Nathan discovers that his job is at risk.

Dwight and Charlotte work on a way to free Audrey from the Sandman's stasis before he can trap her in his mind forever; at the same time, Duke tries to help Darkside Seeker Seth Byrne recover his memories of Haven.

Nathan and Dwight race to rescue Audrey from Croatoan, but the consequences of Duke's dark destiny wreak havoc on their plans. Meanwhile, Vince contemplates an unusual sacrifice.

Two mysterious assaults involve crooked businessmen, and sketching charcoal is found at each crime scene. However, the boy the officers suspect is responsible becomes a third victim, leaving them to pursue a new line of investigation.

Audrey and Nathan learn of a ghost story that wanders the Haven clinic and takes the lives of sick people before their time.

Audrey joins in a friendly game of poker aboard Duke's ship, but the two new players soon lock everyone up and try to find a box that Duke is smuggling. Meanwhile, Audrey's boss arrives in town and demands answers.

A wedding at an isolated estate turns deadly for the guests when the site becomes sealed off and something attacks from within.

Naked savages wander the streets of Haven. While Nathan and Audrey try to determine who they are and where they've come from, Duke convinces the Teagues to let him see the old newspapers and determine who the mysterious "Hunter" is and how he's connected to Audrey.

Desperate conditions in Haven lead to a terrified population that's difficult for Dwight to maintain control over; at the same time, Nathan assembles a task force to restore power to the town; and Audrey tries to put an end to the trouble once and for all.

Nathan receives otherworldly help as he works to track down a terrifying killer; and Duke reaches a crossroads after he has an alarming vision of Haven's future.

Plans for building a new barn are complicated when an old trouble brings the Haven Police Station to life. It's up to Audrey and Nathan to find a way to regain control, but their efforts are hampered when a mysterious killer leaves a wake of bodies right under their noses.

Nathan and Audrey investigate a series of murders, but the prime suspect insists that she's trying to stop the real killer. Meanwhile, in the aftermath of Duke's revelation, Audrey continues to investigate the Colorado Kid mystery involving her mother.