Maddie rollerblades to catch up to Gary and stops when he tries to buy breakfast. She tries to lower the car and drive off, but the car is still hooked to the truck, so she clumsily tries to pull out until Gary raises the car back up. Maddie ends up on probation as a result of her actions, and she is also told she owes a lot in back taxes, so she is in danger of losing her house.
Maddie also works as a bartender at a waterside place in Montauk, where she has lived all her life. She works with her friend Sara (Natalie Morales) and hangs out with her and her husband Jim (Scott MacArthur). Maddie is noted by her boss as having an attitude when she gets into an argument with a customer who tries to buy a drink before the bar is open. On their break, Sara shows Maddie a job listing from a rich family asking for someone to “date” their son before he goes off to college, and in exchange, they are giving away a Buick Regal. Maddie realizes “date” means sex but decides to go along with it because she has no other options, and she wants to exploit the rich since they’re taking her house.
Maddie arrives at the home of the Becker family and meets the parents, Laird (Matthew Broderick) and Allison (Laura Benanti). They discuss their son Percy (Andrew Barth Feldman), who is set to go to Princeton in the fall but is very awkward and shy with little to no friends, and he spends his days in his room playing video games. While they were hoping for someone closer to Percy’s age (Maddie is 32, Percy is 19), Maddie convinces them that she is the right woman for the job. However, Laird and Allison tell Maddie that Percy cannot know about their arrangement.
Laird and Allison tell Maddie to find Percy working at a dog shelter. She wears a form-fitting dress to attempt to seduce him and pretends to want to adopt a dog. Percy shows her a former police dog named Milo that was let go from the force for becoming addicted to cocaine. Percy starts to get nervous as Maddie comes on too strong and tries to leave early, but Maddie offers him a ride home after borrowing Jim’s van. When she brings Percy to her house, he pulls out a can of mace and sprays her in the face. After Maddie painfully explains that she just thought he was attractive, Percy says he just wants to go on a proper date, to which Maddie agrees. Maddie later brings the van back to Jim and Sara, telling them that Percy is “unfuckable”.
Maddie brings Percy to a bar where she knows the waitress and gets him a Long Island iced tea, which he hates. A guy named Travis (Quincy Dunn-Baker) shows up, as he apparently used to date Maddie. He shows off his wedding ring and says that Maddie running out on him was the best thing that ever happened to him, and warns Percy not to get attached to her.
Maddie later goes with Percy to the beach for a skinny-dipping session. While he is reluctant, Maddie coaxes him to join her. Moments later, three drunk teens show up and steal their clothes, which contain their wallets, phones, and keys, so Maddie emerges from the water completely nude and proceeds to fight all three teens before they relent and give her back their stuff. When Maddie goes back in the water, Percy tells her there is something wrong with her. She starts to leave and drive away, but Percy is still nude and demands his phone back. When Maddie won’t give it back, he hops onto the hood of her car, and she proceeds to drive with him hanging on. The cops see them and pursue, but Maddie fears she will lose her license if she is caught, so she drives quickly and manages to run across train tracks before a train can hit them, allowing her to lose the cops.
Maddie brings Percy back to her place in another attempt to seduce him. She tries to do a sexy dance for him, and then has him try to do the same until she sees a rash on his back, which he attributes to anxiety. Maddie applies lotion to his back as he starts to open up about his history, including the fact that his classmates made fun of him for sleeping in his parents’ bedroom and spreading rumors that he was having sex with them, which is why he doesn’t like to go out. Maddie also opens up about an embarrassing memory to Percy.
A former classmate named Doug Khan (Hasan Minhaj) shows up at Maddie’s house, as he is now a realtor and wants to sell her house for full price. Maddie turns him away, as she still plans to save the house.
Percy asks Maddie to spend the day with her for a real date, to which she agrees. They go to an arcade and win prizes before getting kicked out because Maddie was messing with another kid. They go by the lighthouse where Percy asks Maddie to kiss her, and she lets him, though he is a bit awkward with it. She also talks to him about how she never left Montauk and has stayed in the same house as her mom because her father gave it to them along with some money so that they wouldn’t bother him and his new family. They then go to meet Percy’s former nanny, an adult man named Jody (Kyle Mooney). He suspects something is up with Maddie, though she just hits back that he is creepy for being a male nanny to a teenage boy.
Later on, Maddie and Percy go to dinner at a fancy restaurant as part of a little prom date since they both didn’t go to their proms. She encourages him to play the piano after he mentions he can play, so he goes up and plays the song “Maneater” for the whole restaurant to hear, which earns him cheers and applause. Maddie is also equally impressed. A girl from Percy’s school, Natalie (Amalia Yoo), then goes up to offer her praise to him, and she says she is also going to Princeton in the fall. Natalie invites Percy to a party for other Princeton-bound students, though Maddie tries to stop him from going for fear that he will end up sleeping with Natalie or another girl. Despite Maddie’s objections, Percy says he wants to go.
The two take a limo to the party, and Maddie goes looking for Percy, having to walk among snooty teenagers who think she is too old to be there. Maddie eventually finds Percy in bed with Natalie, but he is sick because he’s been drinking and he took an Ibuprofen. She goes to make him throw up until the parents of the kid throwing the party come in to tell Maddie she has to leave. Percy tries to defend her and accidentally ends up punching Maddie in the throat. After they leave, Percy says he is ready to have sex with Maddie in the limo, but after he tells her he loves her, she realizes he is too drunk and refuses to go through with it.
Laird and Allison notice that Percy seems more upbeat and extroverted, which he attributes to his new girlfriend. However, Percy tells them that he is no longer going to Princeton because he wants to stay close to Maddie. Allison calls Maddie, who is beginning to have second thoughts about the job. Laird tells her that she can have the car without continuing the relationship to avoid Percy skipping out on Princeton. Unfortunately, Percy is in his parent’s car and turns it on, activating the speakers so that he overhears their conversation and hears Maddie mentioning wanting to car without having to sleep with Percy, leaving him heartbroken.
Percy then has Maddie come over for lunch to “meet” his parents. He starts drinking their wine and begins to act passive-aggressively before going out with his co-worker Crispin (Jordan Mendoza) to bring the Buick out into the woods to mess with it. They throw a rock onto the gas pedal and make it crash into a tree, which falls on top of the car. When Percy returns to the house, he and Maddie then decide to have sex and get it over with, but before he can even get inside her, he ends up ejaculating on her thigh. He says that he knows about everything and doesn’t want to see Maddie anymore, saying that she will end up living in Montauk for the rest of her life.
Gary later brings Maddie the beaten-up Buick since her name is on the papers. She is forced to continue her Uber duties in her messed-up car while Percy goes back to staying in his room and playing video games. He also won’t return any of Maddie’s texts or calls. After Maddie finally raises enough money to fix her car and pay off her taxes, she celebrates with Jim and Sara, but they announce to her that they are moving to Florida for the sake of their baby (Sara is pregnant). Maddie is left upset as she realizes that she will be all alone.
Maddie later contacts Doug and decides to take him up on his offer to sell her house. She sells it to Jim and Sara so they can stay and raise their baby there, and she is making plans to move to California.
Maddie finds out Percy is at a Princeton mixer and goes to find him. He still refuses to speak to her, even as she tries to explain herself. She hops on the hood of his car like he did to her, and he drives off with her hanging on. They end up driving through a beach where Maddie catches fire from a barbecue grill before Percy drives into the water. He panics and looks for Maddie before they tearfully apologize to each other. After they reconcile, Maddie says she is moving to California, and Percy is happy for her. He also tells her it still counts that he lost his virginity to her, despite the contrary.
Percy packs his bags and says farewell to Laird and Allison on the day he is set to go to Princeton. Maddie shows up to drive him there before she goes to California, and surprises him by showing that she adopted Milo.