Ben Keegan is settling up his daughter Moira's wedding rehearsal at his estate. Peter Novelli, the groom, promises him he will care for his daughter. He asks for some money to set up an extravagant lifestyle for her. Disgusted, Ben walks away. Peter kicks a soccer ball into the woods and tells the workers to clean up. An unseen force throws the now-mangled ball back, but nobody notices.
Audrey and Chris are on a date and take a detour to the wedding to drop off the marriage licenses. Evi and Duke arrive to drop off some wine. Evi and Duke look at Chris and start fawning over him, much to his dismay.
Peter talks to his uncle Dom, who does not approve of him marrying a Keegan. As Audrey gives Peter the licenses, Ben walks up and declares the wedding cancelled, then angrily orders the Novellis to get off his property. As people start walking away, Audrey hears a scream from the bathroom. Inside is blood, debris, and a broken window. She goes outside and finds that her cellphone has no signal and the telephone line has been severed. There is a trail leading into the woods and she follows it.
Duke and Evi approach Beverly Keegan, a member of the Haven Historical Society, and try to ask her if she knows anything about the jewelry box.
Chris follows Audrey into the woods. They find Ben's glasses, covered with a fluid they can't identify. They walk back to the mansion, unaware that Ben's body is hanging from a tree, tangled in vines.
Vince and Dave visit Nathan at the station and say that they are headed for the wedding. They wonder why Nathan isn't coming, then figure that he's jealous of Audrey being with Chris and tease him. Nathan angrily brushes them off, and they leave. Nathan notices that they left behind an advertisement for their Tweet feed.
Beverly admires the box, but says there's nothing supernatural about it. It was made by Regis Glendower or someone from his shop. She offers to buy it.
Chris and Audrey return to the mansion and question Peter and Moira about why he and Ben were arguing. They are defensive, so Chris loses patience and uses his Trouble, making them fawn over him in an attempt to loosen their tongues. Audrey calls him out on this, but it works; Peter had wanted Ben to give him money and land. Peter runs off, so Chris follows him.
Audrey asks Dom if Peter has a Trouble, but Dom says that the Keegans are the ones who are Troubled. He pulls up his sleeves to show that his arms are heavily scarred, then claims that the Keegans did that. They hear a noise outside and investigate. Chris has found Ben's heavily mangled body outside, with marks similar to Dom's. Moira runs off screaming. Audrey wonders why this would have happened to Ben if his family is the one Troubled.
Vince and Dave call Nathan on the radio, using trucker jargon and asking for help because their van broke down on the way to the Keegan's mansion. Nathan agrees to help, as long as they quit spouting annoying trucker jargon.
Most of the staff have evacuated the mansion. Peter and Moira start arguing. The ground shakes and a staff member runs to her car. Vines extend and drag her into the woods, tearing her to pieces. More vines head for the others, and Audrey tells everyone to get into the barn. Dom and Beverly argue, accusing the other of causing this. The vines cover the barn, and Chris warns Audrey that they will eventually break through the walls.
Nathan drives up to Vince and Dave's van and tries to fix the engine. The vines appear and the three get into the van as the vines cover it.
Duke drinks some wine and asks Audrey if she has a plan. She tells him to try to find a way out and asks about Beverly. He says that Beverly did not approve of the wedding. Evi brings up that they were trying to sell the jewelry box, but Beverly needed Ben, because Ben controlled the Keegan's money.
Chris tries to find tools to fight the vines, but Audrey says they should concentrate on whose Trouble is causing this.
Duke and Evi go to the hayloft and try to force the door open. Evi notes that Duke has changed, he wasn't so selfless before. She says it's appealing and offers to run away together to Mexico when they get out of this. They open the door, but the vines are there.
Nathan looks over the van's emergency supplies and asks the brothers if they've heard of animated vines before. They have heard a few myths, then ask if Nathan is jealous of Audrey and Chris getting together. He insists that he isn't, then declares that there is a way out of the vines.
Audrey asks Beverly why the families were feuding. She says that back in high school, there was a fight between Dom and her brothers, and Dom killed her youngest brother. Dom angrily denies it. A vine bursts through the wall, and Duke tackles Audrey out of the way just in time. After a moment, the vine withdraws. Audrey realizes that the vines are animated by the hatred between the Keegan and Novelli families.
Chris and Audrey talk to Moira, who refuses to forgive Peter. The vines start breaking through the walls, and she says that she knew the story of how Beverly's little brother died. Moira then tells them that Ben took her to Packham's Point and showed her the tree that he claimed killed Beverly's brother. Audrey realizes what it means and confronts Beverly and Dom. She accuses Beverly of loving Dom and says that Ben lied to her because he was afraid that he'd lose control of the property and Beverly. Dom finally admits that they were preparing to elope. Beverly is surprised that he was there after all, and Dom explains that her brothers found out about it and attacked him. Then the vines attacked all of them because they were fighting, killing her brother despite Dom's efforts. Beverly apologizes and Audrey tells her she has a chance to make things right. They can use their love to push the plants back if they still have it, and Dom says it never went away.
Audrey gathers everyone at the door. Nathan suddenly arrives, burning through the vines with road flares. He says he only has one left, so get ready to run, but Audrey says that it won't be necessary. Dom and Beverly join hands and walk out as the vines part and recede. Peter and Moira join hands and follow. Duke and Evi join hands and follow. Chris and Audrey join hands, much to Nathan's dismay, and follow. Nathan sadly walks out last.
Later, Dave and Vince do some research and find that the Keegans and Novellis had a common ancestor, which was why both families had the Trouble. Dave tells Nathan not to wait too long to confess his feelings for Audrey. Nathan studies an article on the Colorado Kid murder, then picks up his cellphone.
On Duke's boat, he and Evi share a drink. Duke says that he's thought about her offer, but no, he's staying in Haven. Evi angrily accuses him of having feelings for Audrey, as she's seen him look at her and the desperation and concern on his face when he saved her from the vine. Duke denies this. She asks why he's staying and he says it's because of his father. His father made Duke promise on his death bed to come back if the Troubles ever return, but died before he could explain why. Duke insists that he can't go with her and walks away. Once he's gone, Evi calls someone and tells them that Duke's father never told him. The man at the other end says that they have to keep pushing Duke.
Chris comes to Audrey's apartment above The Grey Gull and offers flowers. He says that he's attracted to her not just because she is immune to his Trouble. She was able to bring two feuding families together and even got through to a cynical loner like him. She is the most amazing woman in the world. Audrey kisses him and they start having sex. Nathan tries to call her cellphone, but they don't notice.
- The Alleged Car: Nathan remarks that his office desk could get him to the Novelli/Keegan wedding faster than Dave's van. Sure enough, it breaks down on the way there, and Nathan ends up trapped with them when he is called in for a rescue.
- Alone Among the Couples: Nathan, as the couples leave the vine-covered barn by joining hands and walking out. Audrey take's Chris's hand, with a shot of Nathan trying very hard not to let it affect him.
- Bad Date: Audrey and Chris were supposed to just quickly drop off the marriage license and go for drinks. It all went terribly wrong, but they reconnect after the Trouble is resolved.
- Dissimile: The Keegan/Novelli Trouble requires one person from each family to trigger it. Vince compares this to epoxy. Dave to...peanut butter cups.
- Don't Go Into the Woods: The woods like to drag people in and when their victims leave alive, they wind up with gnarly scars.
- Everyone Can See It: Vince and Dave poke at all of Nathan's sore spots about Audrey dating Chris, and when he tries to deny everything, Vince tells him that Haven has a lot of secrets, but Nathan and Audrey's Will They or Won't They? relationship isn't one of them.
- Feuding Families: The Keegans and the Novellis
- Financial Abuse: While Beverly Keegan is the matriarch of the family and owns the timberland that has made the family wealthy, it is her nephew, Ben, who has control over the finances. Including what she is and is not allowed to purchase, as Duke and Evi discover when they attempt to sell her the box they found in the Rasmussen House.
- Gold Digger: Peter is a rare male variety.
- Hollywood CB: Dave appears to have picked up all his CB radio knowledge from watching old movies, because he insists on using trucker speak, including overuse of the word "over" and assigning Nathan the handle "Baby Bear." Nathan tells him he'll only come out to help if he stops talking like that and gets off the radio, presumably because it's on the same frequency as the one in the police precinct.
- Insert Song: "Alegebra" by A Camp over the end scene with Audrey and Chris.
- Jerkass: Chris, which is his main character trait, but it should be noted he's this way towards Audrey...the woman he is trying to date.
- Kissing Cousins: The Novellis and Keegans are distantly related. The Novellis had a set of twins who were Troubled, several generations back, and one of them married into the Keegans and now the Trouble is only activated when there is discord and one member of each family is present. Which tracks throughout the episode (the vines appear when there is discord between a Novelli and a Keegan), but is the only time in the series in which a Trouble is split this way.
- Mother Nature, Father Science: Audrey and Chris play opposite sides of the field here, where Audrey insists the roots come from the people they're trapped with and Chris wants to take a more scientific approach. And he's kind of a jerk about it. Chris eventually comes around to Audrey's side, however.
- Nature Is Not Nice: One of the scenes in the cold open shows Peter kick a soccer ball into the woods, only for the woods to return it mangled.
- Noodle Implements: Nathan busts Dave and Vince out of the root-covered van with duct tape, a hockey stick, and two road flares.
- Operation: Jealousy: It's implied Vince and Dave push all of Nathan's buttons about Audrey's date with Chris to motivate him to cut them out of the root-covered van. It works.
- Parental Marriage Veto: Neither side approves of the marriage, but Ben Keegan goes as far as to rip the marriage license out of Peter's hands and crumple it up, calling the wedding off and ordering Peter out of his house.
- Redundant Rescue: Nathan fights his way through the roots on the outside of the barn to Audrey and the others, only to find that she's already figured out who the Troubled person is and how to make the roots go away.
- Relationship Upgrade: For Audrey and Chris.
- Shipper on Deck: Dave tells Nathan not to wait too long to tell Audrey how he feels about her.
- Technobabble: Chris's scientific explanation about the goo found on Ben's glasses in the forest comes off as way more sure and authoritative than it should, since he has no way to test the material and is making this assumption by sight alone.
- Unable to Support a Wife: Peter, the young groom, is criticized as this by his future father-in-law.
- Wait for Your Date: In an interesting twist on the trope, Chris is waiting not for Audrey to get ready, but for her to stop working.
- When Trees Attack: The Trouble of the week manifests as tree roots emerging from the forest to kill people.
- Young Love Versus Old Hate: Subverted. The young groom is marrying the bride mainly for her money, while the real love story is between the feuding aunt of the bride and uncle of the groom.
