Doctor foster 4 Gemma is thrilled that her life is returning to normal and enjoys watching her family, feeling content to be together again. However, at work, her colleague Ros questions how Gemma could reconcile with her husband despite a big secret between them. It’s strange since Ros was the same person who asked her to forgive Simon. Gemma defends her choice, saying they have a long history and a child together and she has to stay to help him with the financial problem. However, another issue arises when her colleague Nick informs Gemma of a new complaint against her, which is serious because this time it’s in person. The complaint is anonymous and deeply personal, making Gemma think the accuser must be someone she knows. Gemma checks negative reviews about her online, and is speechless at how bad they are when suddenly one of the patients, Gordon, comes in and asks for a visit for his feet. At home, Simon tells Tom how he and Gemma first met, while Gemma struggles to prepare the most unhygienic and undercooked rice. They met in a pub where Gemma, drunk, began to dance on a chair and fell off. Simon helped her up and suggested they go for curry. Gemma finishes making the dishes and brings them to the table. Simon finally realizes they're having curry today and remembers it's their anniversary, which he had seemingly forgotten. However, it's just an act, because he then shows Gemma a card he had hidden under her dishcloth. Touched by the gesture, Gemma and Simon become romantic in their bedroom after dinner. However, when they cuddle, Simon's phone chimes. He texts back immediately and tells Gemma it's just work, but she doubts it's not. The next morning, Gemma faces a disciplinary meeting due to a complaint made by Carly's ex-boyfriend, who mentions that Gemma threatened him with a lit cigarette. The GMC's concern deepens with additional context from online comments and police inquiries related to Simon's mother's suicide. They suspect that Gemma was the one who gave Helen the sleeping pills she used to kill herself. gemma is given the choice between taking an informal leave and facing a forced suspension and chooses to leave immediately. Gemma realizes that Ros is not her ally and had informed the police about her after seeing some sleeping pills in her bag the other day. Gemma tells her that the pills Ros saw were the ones she took from Jack when he tried to kill himself. Ros apologizes to her and says she will talk to the police again. Gemma leaves her office and sees Gordon. He's upset to learn that Gemma is leaving for a while, and she tells him to look her up online to understand why. Feeling desperate and isolated, Gemma visits Carly hoping for support, but instead, she finds her supposed ex-boyfriend answering the door; they have gotten back together after all the struggles Gemma has gone through to help Carly out of her abusive relationship. Gemma begs them to withdraw the complaint and even offers to pay, but Carly rejects her and tells her to stop using money to buy people. Despite having a bad day, Gemma still goes to Tom's football match, where she meets the Parks family and her husband's mistress, Kate. She greets them and can't help but notice how overdressed Kate is for a children's football match, clearly not there just for the game. Gemma approaches Simon to talk about her suspension and the negative reviews she's received. Simon hugs her, but their moment is interrupted when someone calls him. Gemma notices how tense and focused Simon becomes when answering the calls and texts, which he claims are work-related, yet he snaps at her, angry that she doesn't trust him. Later, Tom heads to the car park and decides to get into Simon's car because he can't talk about football with Gemma, but Simon claims he has a work issue and must leave. Gemma knows it's not work-related and, feeling upset, drives Tom to get some pizza. Tom expresses admiration for his dad, suggesting Simon must work very hard. Gemma is even angrier and decides to drive to Simon's office to confront him. She finds Becky and confronts her about covering for Simon. When she can't find Simon in the office, Becky reveals that Simon and Kate are in the garden behind the building. Gemma watches them kissing from a distance, completely devastated. She makes Becky reveal that she was with Simon, Kate, Anna, and Neil on holiday at Kate's parents' villa in France. Kate's parents don't know about her and Simon's affair. At that moment, Tom bursts in and asks where his dad is. Gemma doesn’t know what to say and keeps looking at the loving couple in the garden. Tom is such an ungrateful kid and shouts at her as if it's her fault his dad isn't here for him. Gemma is so done with this father and son and tells Becky to inform Simon that his son is waiting for him and she has to leave now for a work conference. So Simon will have to take care of his ungrateful son, but Gemma can't do that to her son. She comes back and tells him she was lying and she just actually needs some time away as she can't handle everything that's happening right now. Gemma drives away and cries in her car. Simon keeps calling her, but she doesn’t pick up. Gemma goes to meet Jack, who is enjoying his vacation in a coastal town where he is spearfishing. He brings her back to the house where he is staying and she sees Mary, someone close to Gemma, as her photos are all over the house. Mary is a close family friend who has supported her since her parents died in a tragic accident. They talk about Jack and his grief over losing his boyfriend, David. Becky sent the pictures of the holiday in France. Gemma scrolls through them, zooming in on a sign behind Becky that says “La Pierre Blanche”. Just at that moment, Jack walks in and makes fun of her for always being on her phone, but she quietly shows him the pictures. Jack talks about how his health has improved since he got here and stopped drinking, so he wants to live in this town. Mary and Jack then talk about what Gemma should do with her marriage. Jack thinks she should take Tom and leave. Gemma says she wants to vanish and never come back. Gemma goes on to say that her loss is so much harder to deal with than Jack’s boyfriend who died. Jack is mad, and Mary tells her she has to be careful when she's upset because she always hurts people. Gemma goes to bed but can't sleep, so she decides to go out and walk along the beach. Alone on the beach, Gemma is overwhelmed by her loneliness. Her solitude is interrupted by a call from Simon. She asks him if he has anything to confess, but he still denies everything. She hangs up and cries from the depths of her heart, pained by the realization of the kind of lying monster she has intertwined her life with. She walks toward the ocean, attempting to drown herself in its depths. Jack emerges, calling out for her. He discovers her phone on the beach and panics, but a soaking wet Gemma walks toward him. She had intended to drown herself but ultimately changed her mind. She goes back inside to change her clothes, then drives home. She picks up Tom and meets Becky at the school. Upon returning home, she dresses up. Simon arrives home, clueless about the day's events. He is surprised to see her already back. She asks him to get ready for a dinner date. Simon, unaware of with whom or where, still goes upstairs to change his shirt. He goes downstairs and finds Becky and her daughter already at their house. Gemma tells him she asked them to come over to take care of Tom. Then, she drives a clueless Simon to a place she claims will be a surprise to him. The climax of her plan unfolds as they arrive at the Parks' house for dinner, a dinner that was actually scheduled for the following week. Although Simon is reluctant and Kate's car being at home means she is also there, Gemma steps up to ring the bell. Susie and Chris, despite the unexpected visit, warmly welcome them nonetheless. Simon and Kate act very awkwardly around each other during the dinner, while Gemma is excited to observe.