On Saturday afternoon, Susan heads out for a walk alone and finds herself at Coal Place, where Venetia and her husband live. Outside their cottage, she sees two police officers leaving. Venetia, appearing dazed, waves Susan over, apparently mistaking her for someone offering condolences. Feeling trapped by politeness, Susan enters.

In the sparse living room, Venetia introduces her husband, Felipe. He explains that the police were asking about potential disputes involving Aimee and Rory and that he and Venetia must provide DNA and fingerprints to eliminate them as suspects. When Venetia learns Susan’s identity, she coldly dismisses her apology, pointing out that her sister is dead. Felipe comforts Venetia as she orders Susan to leave.

Susan arrives home to find Greta and Jon in close conversation that stops abruptly. She recounts the confrontation with Venetia. Jon criticizes her visit while Greta researches Venetia and Felipe online. Susan expresses her need to determine whether her message led to Aimee’s death or whether Savannah was killed in a case of mistaken identity. Greta finds a news article featuring local politician Albie Byrne and reveals that he’s Savannah’s ex-husband.

Jon falls silent as Albie’s name surfaces, dredging up memories of Greta’s car accident—which Susan now privately blames on Jon. Reading the article, she finds Albie quoted saying that “no woman should feel unsafe” answering her own door (99). The words chill Susan as she imagines Savannah opening the door to her killer, and she wonders if she was the real target.

Venetia wakes from medication-induced sleep on Saturday, disoriented on the couch. She confirms with Felipe that Susan’s visit was real. Felipe reveals what he discovered online while she slept: that the murdered woman, Savannah, lived at 26 Oakpark, the same address as Susan.

On Sunday, Susan shops at a supermarket with Bella sleeping in the trolley. When she returns from retrieving tinned tomatoes, the trolley and Bella have vanished. Panic-stricken, she searches adjacent aisles and alerts a staff member. She finds the trolley with Bella still asleep in a different aisle. As Susan leaves, shaken, she glimpses a vaguely familiar figure exiting the store but cannot place them.

Leesa tells Susan that she has arranged a visit to Moira Fitzpatrick, whose son was injured while being babysat by Cody. Susan reluctantly agrees to come.

Moira welcomes them and readily shares the details of the incident. Cody, then 14, locked her four-year-old son, Senan, outside over a television dispute. Senan wandered from the garden and was hit by a reversing car, suffering a broken rib, concussion, and bruising. Moira calls Cody a “psychopath” and shows nanny-cam footage corroborating the incident. While walking home, Leesa remains skeptical, noting that maternal protectiveness can cloud judgment.

On Sunday evening, Celeste hosts the Sullivans for dinner. Cody arrives home and mumbles a brief greeting before disappearing, prompting Juliette to make pointed remarks about parenting. Nika enters with polite grace, deftly deflecting Juliette’s questions about romantic interests, and Celeste sends her away. Juliette then reveals that Zach, the boy Nika was seeing, is actually the boyfriend of Nika’s friend Ariana. Nika’s friend group has rallied around Ariana, leaving Nika isolated. The news deeply unsettles Celeste.

On Sunday evening, Jon retrieves the bracelet from Susan’s drawer to examine it. Upon hearing her arrive, he fumbles to replace it, drops it, and barely manages to close the drawer as she enters the room. She meets his conversational attempts with one-word responses. Susan takes tea and chocolate into the den—a room they use only when watching separate shows—and suggests that Jon go for a run. He leaves, certain she knows about the affair.

On Sunday evening, Maeve watches social-media attacks against Nika on her laptop. A classmate posts a veiled threat about hiding walnuts in someone’s lunch if they have a tree-nut allergy. Maeve is horrified but feels slightly “thrilled.” Her aunt Greta arrives, takes a phone call in the hall, and looks stressed; Maeve suspects that the caller was Jon. When Maeve goes looking for Greta, she returns to the living room to find Greta examining her open laptop. Maeve freezes and then reassures herself that she had already closed the browser tab.

After the Sullivan dinner, Nika checks her phone and finds that she’s been added to a hostile Snapchat group filled with hateful messages from her entire friend group, including demands that she kill herself. She blames Susan for the situation and wonders whether Maeve fed Susan information as a deliberate act of revenge for past bullying. After Celeste comes to ask about Zach and Ariana—and Nika lies, saying that everything’s fine—Nika’s phone floods with new notifications. She decides that she needs to create a bigger distraction and retrieves something she has kept hidden under her bed.

On Sunday night, assuming that Jon has gone to his mistress, Susan reflects on her hatred for the unknown woman, convinced from where the bracelet was found that she’s been in their home. She hears noises outside but dismisses them. After checking Bella on the monitor, she goes upstairs to check in person and then returns downstairs, where the quiet house feels eerie. She closes the living room blinds. Glancing at the baby monitor again, she freezes: A shadowy figure stands over Bella’s crib on the screen.

Susan runs upstairs, grabs Bella from her crib, and flees outside. She feels safer standing in the driveway as Jon arrives home. She breathlessly explains what she saw. Jon reveals that the baby monitor has a time delay—she saw herself checking on Bella moments earlier. Susan feels foolish.

On Sunday night, Venetia obsessively researches Susan online while Felipe tries to stop her. Using Susan’s phone number from the original screenshot, she tracks her across platforms. On a parenting forum, she finds a three-month-old post where Susan confessed to having intrusive thoughts about hurting her newborn—admitting that she understood how people could become violent. Venetia sees this as exploitable. Her thoughts escalate from making Susan believe that something bad might happen to her baby to a darker conclusion: It would be better if something actually did.

Five days earlier, Venetia visited Aimee, who excitedly revealed that she was eight weeks pregnant. When Rory texted that he was coming home early, Venetia urged Aimee to leave him, reminding her of his past abuse, including a miscarriage caused when Rory pushed her down the stairs. Aimee defended Rory but finally agreed to leave the next morning while he was at work. Rory then arrived home, and Aimee panicked, urging Venetia to slip out the back. From the side passage, Venetia peeked through the window and saw Rory with his back to her and Aimee on the couch. It was the last time she saw her sister alive.

On Monday morning, the moment Jon leaves for work, Susan begins investigating his affair. On their joint credit card, she finds a second charge from the Marker Hotel. Knowing that he would use his personal card for most purchases, she searches for his login credentials, finds them in an old shared spreadsheet, and successfully accesses his bank account on her phone.

Susan examines Jon’s credit-card statements and finds hundreds of euros spent on intimate lunches, dinners, cinemas, and coffee shops—places they never visit together—along with a charge from Boodles, a jewelry store, confirming that he bought the bracelet. Unable to access his email, she decides to track his current location using the AirTag on his keys. That afternoon, Bella suddenly cries out. Susan finds four bright red marks on her arm resembling fingerprints, which fade quickly. Concluding that she must have accidentally hurt Bella while comforting her, she feels like a failure. Then, the doorbell rings—it’s Felipe.

Felipe apologizes for Venetia’s behavior and tells Susan that her address has been shared online. He explains that Venetia struggles with emotional regulation. When Susan confirms that she genuinely saw Aimee with Warren, Felipe seems baffled, expressing certainty that Aimee was faithful to Rory. He advises Susan to stay away from Venetia.

That evening, Jon arrives home unusually early, making Susan suspicious. While he’s upstairs, she takes his keys and links his AirTag to her phone.

Nika retrieves Maeve’s diary from under her bed, where it’s been hidden for nearly five years. She stole it on Halloween when she was 13 and helped Maeve search for it the next morning while quietly beginning to ghost their friendship. Now, she decides that the time has come to use what she found.

Nika opens the diary to an entry in which Maeve confesses to having a crush on Ariana. She creates an anonymous Snapchat account called “AWGoss” and photographs the page. She believes that posting it will devastate both Ariana and Maeve while diverting all negative attention from herself.

On Monday evening, Jon enters the living room to find Susan reading. She declines his offer of tea. When he considers where to sit, Susan stretches her legs across the entire couch, physically blocking him. Jon announces that he’s going out for air, and Susan tells him to take his time.

The moment Jon leaves, Susan opens the AirTag app and watches his location move through Oakpark. While waiting, she browses an online message board and finds threads full of victim-blaming comments about Savannah and speculation that the same car was seen at both murder scenes. She checks the app again and sees Jon’s location returning—moving up their driveway and appearing inside the house. However, she hears no sound of the door. Susan suddenly realizes whose house he’s actually in.

On Monday, Maeve receives a Snapchat notification from an account named “AWGoss.” A video begins, showing a hand opening her diary to reveal her name and address on the first page. Set to Katy Perry’s song “I Kissed a Girl,” the video flips through pages and zooms in on Maeve’s entry about her crush on Ariana. Her entire school year has been tagged. Maeve runs to the bathroom and vomits.