Plot

Out in the wilderness plan a dark arts slumber party. Natalie and Misty tame a stallion. On Halloween night, Shauna parties like it's 1996.

In 1996, the girls dance to Montell Jordan's "This Is How We Do It". But after a few minutes the batteries on the Walkman fail, leaving them disappointed. They hear a noise from the attic and Mari thinks it's the spirit of the dead man. Natalie mocks her by saying that maybe it's the dead guy's missing fingers. The girls get more creeped out and Ben tells everyone they should just sleep.

In the morning, Misty goes in to the room where Ben is sleeping. He has an erection. As she reaches for it, Ben wakes up and yells at her. Natalie nudges Jackie to wake up. Jackie complains of menstrual cramps and Natalie says that they're all having them. A reluctant Jackie is sent to get water from the lake. She find Lottie stand immobile in the water. Jackie is concerned for her. Shaunu arrives and asks if Jackie needs help with the water. Jackie notices that Shauna seems more "chipper" than the others and Shauna says that she hasn't gotten her period yet. Jackie comments that "Good thing you're a virgin or we'd really be in trouble."

Taissa catches Shauna dipping a menstrual rag in some blood from a killed animal. Shauna shows the rag to Jackie saying "Thanks for jinxing me", implying that she's gotten her period too. While the other girls work, Jackie sits fiddling with the dead Walkman. Shauna takes Jackie aside to show her how to butcher one of the animals, a task that Jackie finds too gross to engage in. Shauna tells Jackie that she has to find a way to contribute because the other girls are noticing that Jackie isn't doing her share of the work. She gives Jackie a pep talk, saying that Jackie has always been good at inspiring people.

Van and Taissa make out behind the cabin. They hear a scream. Mari comes running out of the cabin. She says that she was standing under the trap door to the attic when she felt something fall on her. The girls can't find anything on her and Taissa mocks Mari's belief in a ghost. Jackie suggests that they hold a seance in the attic in order to get over the fear of the attic. Taissa think's it's a dumb and immature idea and Laura Lee warns against dabbling with the occult, but the other girls agree. Shauna and Jackie begin preparing the attic, putting candles on a set of symbols which have been carved into the floor. Misty gives Ben a drink to help relieve swelling in his leg.

Natalie and Travis hunt for more food. They joke and tease each other. Eventually they kiss. The girls have the seance, greatly enjoying themselves as they ask banal questions about their lives. Taissa and Laure Lee sit downstairs, the only ones who aren't participating. Laura Lee reads the flight manual for the plane they found. Taissa says that Laura Lee is even crazier than the other girls if she's thinking of flying the plane. Suddenly, Lottie screams. She's catatonic, rocking back and forth saying "It wants" over and over again. Then she begins speaking in French. Jackie, who was in French class with Lottie but was a poor student, tries to translate, saying that Lottie is saying something about blood. She then goes to the window and bashes her head against it, cutting herself on the glass. Laura Lee begs Ben to make the girls stop but he is sick and vomits. Laura Lee grabs her bible and rushes upstairs, yelling at Lottie "The power of Christ compels you". She then throws the bible at her. This does the trick, with Lottie coming out of her trance like state, seemingly oblivious to what has happened.

Ben confronts Misty about why she poisoned him. She admits that she has feelings for him. Ben tells her that he has feelings for her too and that he got angry at her because he's afraid he can't control himself around her. He tells her that because she's underage and also her teacher that he can never cross that line, even if he wants to. He warns her to keep this a secret from the other girls, lest they be jealous. As they prepare for bedtime, Taissa decides to sleep in the attic to prove to the other girls that there's nothing to fear. Shauna decides to go with her. Up in the attic, Taissa reveals that she's figured out that Shauna is pregnant and warns that if they're stuck there much longer, the situation will become obvious to everyone.

In the present:

It's Halloween. Shauna texts with Adam, who invites her out to a club, while her daughter Callie wants to go into the city with her friends. Shauna tells Callie that she has a book club meeting that night. Jeff agrees to hand out candy on his own to allow the women to go out.

Natalie gets a call from Kevyn. He tells her that he got the file on Travis' death and that the toxicilogy report shows Travis was sober when he died. Kevyn tries to invite Natalie out but she cuts him off saying she has another call. Natalie calls Misty and asks her to get her contact to hack into the police files. Misty is at work at the nursing home and scares some kids by faking a medical emergency with a patient.

Taissa discusses with Simone how she's behind Bathurst in the polls. Their dog begins barking at something. Taissa goes out to investigate and finds that someone has written "Spill" on their door in red paint. Later, after coming back from trick or treating, Simone suggests that Taissa use the information about Bathurts daughter's drug addiction. Taissa seems reluctant. When she goes into her son's room she finds a jar of red paint under his bed. She and Simone confront their son about why he painted that word on their door. He denies it, saying that "the lady in the tree" did it. When Taissa says that there's no lady in the tree, he storms off. Taissa and Simon discuss what's happened. Simone worries that Taissa is being distracted from her family. Taissa decides to call a press conference the next day and announce that she's quitting her campaign.

Misty goes to Natalie's place and gives her a gift of an aroma diffuser. She tells Natalie that her contact, someone she knows from an internet message board, got the files, but now he wants an in person meeting. They meet at a restaurant. The contact says that he got spooked when he discovered that the man he stole from was a cop. He says that he will give them the information if they let him in on the investigation. Natalie spills a cup of gasoline on him and threatens to light him on fire, making him hand over the file.

Shauna and Adam go out to the club. They're dancing and having a good time when Shauna sees Jackie across the crowded club. She chases her down and finds out that it's her daughter Callie, dressed in a Yellowjackets uniform that she found in Shauna's closet. Adam comes up and embraces Shauna. Callie realizes that her mom is cheating on her father. Shauna takes Callie to go somewhere so she can come down off of the drugs she's on.

Natalie and Misty review the file of Travis' suicide. Misty notices something in several pictures of the floor around where Travis body was found. There appear to be remnants of wax, as if candles had been lit. Sketching out the location of the candles, they discover that they are in the shape of the symbol from their time in the wilderness.

Shauna and Callie talk about what's been going on. Callie suggests that Adam is interested in Shauna because of the Yellowjackets. Shauna says that he doesn't know about that, but Callie says that he probably looked her up on the internet. Callie asks when her mom fell out of love with her dad. Shauna says that there's a lot of baggage between them. Shauna asks why she and Jeff never talk about Jackie. Shauna reveals that the Yellowjackets uniform Callie is wearing was Jackie's, not hers. Jackie's parents gave it to her on what would have been Jackie's 40th birthday. Callie reveals that she notices how unhappy her mom is and that it's not okay what happened to her in the wilderness.

Taissa holds a press conference outside her home. As she looks at her prepared remarks, announcing that she will be quitting the campaign, her vision begins to swim. She changes her mind, showing the graffiti on her home and making an angry and impassioned speech announcing that she's staying in the race. She sees a woman, bleeding from her eyes, standing across the street.

The morning after Halloween, Callie tries to blackmail her mom, saying that she will reveal that Shauna is cheating if she doesn't allow Callie more freedom. Shauna explains to Callie what life will be like if her parents divorce, including having to spend time at her father's sad sack bachelor pad. An intimidated Callie confesses to Jeff that she snuck into the city but keeps silent about Shauna's infidelity. Shauna searches on the internet to see what kind of information Adam might have found about her.

Taissa visits Natalie. Natalie shows her the images from the scene of Travis death, telling her how they form the symbol. Taissa asks who might have done that. Just then, they both get a text message from an anonymous source. It tells them to collect $50,000 and await instructions. It includes an ASCII version of the symbol. Taissa calls Shauna to inform her about what's happened and learns that Shauna already heard about it from Misty. Natalie derides Misty as a "conniving poodle haired freak". Unbeknownst to them, Misty is watching on a spy camera hidden in the gift she gave Natalie.