The film opens on a shot of Santa Barbara, California and were told it's the year 1979.
Dorothea (Annette Bening) and her 15-year-old son, Jamie (Lucas Jade Zumann) are inside a grocery store while outside, their Ford Galaxy car is on fire. Everyone In the parking lot scrambles to help as Dorothea and Jamie explain, in voice-over, that this was the car that drove Jamie from the hospital. Dorothea was 40 when Jamie was born, and everyone said she was too old to be a mother. She recalls telling Jamie, as a baby, that the world was big and there-s a lot to explore. Jamie tells us his parents are divorced and he hasn't seen his dad in five years. Now it is just his mom and him.
Dorothea thanks the firemen who put out the fire. She invites them over to her birthday gathering that evening. Dorothea laments that the car was beautiful but Jamie points out it smelled like gas and overheated all the time. He tells her its not normal to invite firemen to dinner.
We meet the 17-year-old Julie (Elle Fanning) as she sits, bored, at a therapy session for teen girls. She leaves, lighting up a cigarette, riding her bike. At an OB-GYN office, 28-year-old Abbie (Greta Gerwig) takes a photo of her doctor as he puts a swab into a tube and writes down her name. She goes home to the house she stays in and plays rock music loudly. Julie enters the same house and is told by the home repair guy, William (Billy Crudup), that Jamie isn't there. Julie visits Abbie's room instead. Abbie takes a picture of Julie even though she tells her not to. Abbie explains she's taking pictures of everything that happens to her in a day.
Dorothea and William get home with groceries and tell the other three about their car bursting into flames. Abbie lets Dorothea know she'll be late on her rent. Dorothea tells her not to worry about it.
Jamie and Julie go up to his bedroom and lay next to each other. She traces her finger over his hair and nose and chest and they touch hands but when he tries to grab her leg, she pulls away and tells him she liked it better before he got old enough to be horny. Julie tells Jamie that friends cant have sex and still be friends, adding that she likes them as they are. Dorothea calls Jamie downstairs to set up for the party and Julie comments that she's compensating for her loneliness. Downstairs, Dorothea compliments William on the work he's doing on repairing the ceiling.
That evening, many arrive for Dorothea's birthday party. She chats up the firemen, telling them about the history of her home. William and Abbie bond. In the kitchen, Dorothea asks William about a car he can loan her to replace the one that caught on fire; he suggests a 49 Deluxe in exchange for rent.
In voice-over, Jamie tells us that his mother was born in 1924 in a time with no television or money. When she was16, World War II broke out and she dreamed of being an Air Force pilot. She went to flight school but the war ended before she completed the training. She became the first woman to work in the drafting room of Continental Can Company. She met Jamie's dad, had Jamie, and then they divorced. We see an eight-year-old Jamie with Dorothea as she tries to open a bank account in his name but is refused because he's just a little guy. She tells them he's a person who has volition and autonomy and privacy who needs a bank account. When shes called into the principal's office because a 13-year-old Jamie has skipped school, she asks why he's not allowed to skip school. The principal says he needs to provide a note with her signature and not a forgery. At home, Jamie shows his mom how he traced her signature from a check and she finds it ingenious. She then provides genuine notes to excuse Jamie from school with crazy excuses (volunteer work for the Sandinistas; involved in a small plane accident) to show how she feels about the school's policy.
We flashback to Dorothea introducing Jamie to William, hoping that, as he renovates their house, he will become a male role model for him. We also learn that Dorothea writes her stocks down every morning with Jamie's help. He also tells us she smokes and never dates a man for very long. In the present, Julie leaves the party. Dorothea knows Jamie's in love with her and tells him having his heart broken is a tremendous way to learn about the world. While doing the dishes that night, Jamie asks "Do you think you're as happy as you thought you'd be when you were my age?" She tells him not to ask people questions like that because wondering if you're happy is a great shortcut to being depressed.
Jamie and Abbie stay up late listening to vinyl records of punk music. Dorothea enters their room and asks them what it is. Abbie tells her, "It's the Raincoats". Dorothea asks why it can't be pretty. Jamie tells her pretty music is used to hide how unfair and corrupt society is. Dorothea points out the music isn't very good. Abbie says the band doesn't want to be skilled but just likes creating energy that is raw.
Dorothea tells us Jamie was born in 1964 with a meaningless war (Vietnam), protests, Nixon, computers, drugs, boredom. She feels she knows him less every day. We see Jamie playing the fainting game with other kids where someone pulls on your diaphragm until you faint. But when Jamie tries it, he falls and doesn't wake up for 30 minutes. He is brought to the hospital and recovers. The next day, Dorothea asks him why he did something so stupid. He counters by asking her why she smokes too much as if she is trying to smoke herself to death and why she's fine being sad and alone.
Worrying that she can no longer connect with her son, Dorothea talks to Julie and Abbie in her kitchen and asks if they can help him figure himself out and be a good man. They suggest William help but Dorothea thinks Jamie connects with Julie and Abbie more. Dorothea drives until she finds Jamie skateboarding and tells him that she asked Julie and Abbie to help him with life. He gets angry and runs off. He finds his skateboarding friends and asks if they're still going to Los Angeles.
In Dorothea's home, William gets a phone call that Jamie went to L.A. to see a concert with his friends. Dorothea says he's mad at her and this is his way of dealing with the disconnect he feels for her. That night, Julie climbs up the window and sneaks into Jamie's room. He's still out of town so she gets undressed and gets into his bed. Nearby, William joins Abbie in her room, where she shows off her photographs. Arbitrarily, she asks if he wants to fool around with her and he says, yeah. She tells him shes recovering from cervical cancer and then they begin kissing. Jamie returns home and finds Julie in his bed. He tells her he was in L.A. and tries to kiss her. She stops him and tells him she's upset because a boy came inside her.
In a flashback, we see Julie hanging out with friends and then alone in a car with a boy; she sits up and asks if he just came and he apologizes. In the present, Jamie asks what she's going to do but she says until be fine. Julie reminds Jamie that she was asked to help raise him; she asks him what he would say to her if she was his mom. He says he would tell her he doesn't need any help and is okay.
In Abbie's room, she asks for William to come up with a story for them to have sex to. She decides he will be a photographer and start touching her inappropriately. They role play. Later, they have loud sex which everyone in the house overhears, including Dorothea, who is up late, thinking.
In another voice-over, Jamie tells us he met Julie when they were little. Her mother is a therapist and she has to attend teen group sessions. Julie was changed when her mom got remarried and also when her half-sister was born with Cerebral Palsy. She then began fooling around with boys and sneaking into Jamie's house. She works at the mall, selling potpourri. We see her reading the book 'Forever' by Judy Blume.
The next morning, Julie climbs down from Jamie's window and goes in the front door, letting us know that she spends the night discretely. At breakfast, Abbie asks about Jamie getting home safely. Dorothea tells her she couldn't sleep so she was listening for him, hinting that she heard Abbie and William loudly having sex. Jamie emerges and she asks him to tell him next time he goes out of town so she doesn't make so much dinner. She then convinces him to do the stocks with her, as is their normal routine. When they're alone, she asks Jamie if he can escort Abbie to her doctor's appointment since Dorothea will be at work. Jamie is worried shell get bad news about her cancer. Dorothea tells him, "Men feel like you have to fix everything for women, or you're not doing anything. But some things cant be fixed. Just be there. Somehow, that's hard for you all." He says he's not all men; he only represents himself. She responds with, "Well, yes and no."
At the OB-GYN, Abbie is told her cancer is benign but she has an incompetent cervix and it may not be strong enough to go full term during pregnancy. Back at the house, Abbie asks Dorothea if having Jamie was the biggest thing that happened to her. Dorothea tells her she guesses it was but Abbie will get through it; this is the hard part but then it gets better. She then adds then it will get hard again and wonders if she should have thrown that in. Abbie reveals she has purchased two birds a boy and a girl that will be monogamous for life. If one dies, the other will die a week later.
Dorothea asks Jamie about his trip to the doctor with Abbie. He says he learned a lot and we flash back to him in the waiting room, next to a pregnant teenager. This reminds him of Julie and him visiting the pharmacy to pick up an E.P.T. pregnancy test. He brings it to Julie's bedroom and tells her how it works (since they weren't very common back in 1979). They have to wait two hours for results so they go to the creek and she teaches him how to smoke a cigarette. She tells Jamie she thinks being strong is the most important quality a man can have not vulnerability or sensitivity or even happiness. When they return to her room, they learn that she is not pregnant.
At his home, Abbie thanks Jamie for joining her at the doctor by giving him a mix tape. He tells us that he bonded with Abbie that night and learned she grew up in Santa Barbara but then moved to New York City In 1973 to go to art school. She fell in love with photography, then with her teacher, then had an abortion. Her friends couldn't deal with her cancer so she went back home. Her mom reveals she took DES when she was pregnant with Abbie and that it probably led to the cervical cancer. Her mom feels so guilty, she never talks about Abbie's cancer with her so Abbie looks for another place to live which is how she ended up in an upstairs room at Dorothea's.
At her job, Dorothea is the only female employee. A co-worker asks her out and is surprised when shes open to the idea, stating her coworkers had wondered if she was a lesbian. Back at home, Dorothea sees Julie climb down from Jamie's room. As Julie walks home, Dorothea pulls up in her car and asks Julie what she does with Jamie. Julie says she just sleeps and they talk. Dorothea and Julie then sit in Dorothea's car. When Dorothea begins to smoke, Julie asks for a cigarette. Dorothea tells her its bad for her. When Julie replies that Dorothea smokes all the time, she responds "When I started, they weren't bad for you. They were stylish and edgy so it's different for me." Julie asks Dorothea if she has moved on since Jamie's dad. Dorothea says she had love twice but that part of her life just never worked out right.
At home, Jamie asks Dorothea where she's been but she lies and tells him she was just out running errands. He has done the stock list without her, which makes her happy. Dorothea invites Abbie to go out with her that night and William asks to come along. The three of them go to a bar where Dorothea looks for a man to date. William leans in and kisses her.
A punk rock band plays. Dorothea tells us that she's 55 years old and this music is what her son believes in. She tells us, "It's 1979 and in 1999, I will die of cancer from the smoking". She adds in voice-over that people don't know punk will come to an end and Reagan will be president and the fear of a nuclear war will end and HIV/AIDS will become a thing and there will be new skateboard tricks and the Internet.
Jamie returns home and tells Jamie the club was life-changing. She continues to narrate, telling us she will prepare for Y2K before she dies [in 1999]. That she will put $16,000 worth of gold coins into a safe deposit box. That she died before the millennium officially began.
Abbie comes home and finds Julie in Jamie's bed, which surprises her. They tell her they were just sleeping. Abbie has come in to give Jamie advice to get out of their town if he wants to ever have a chance at an interesting life. She tells them that at the club, she ran into an old friend who spat on her so she hit her and they got into a fight. They ask why she spat on her and she tells them that right before she moved to New York years earlier, Abbie had spat on the friend, thinking she'd never come back so it wouldn't matter. She tells Jamie that William then told her he didn't want to sleep with her anymore. Abbie then tells Julie she wants to talk to Jamie alone and she leans in to tell Jamie not to let Julie sleep there without having sex with him because its disempowering. She adds that he should get out of the town before he ends up working at a sunglasses shop.
The next morning at breakfast, Abbie gives Jamie some books from her feminism class, as her attempt to parent him, as Dorothea requested. Jamie begins reading Our Bodies Our Selves; Sisterhood Is Powerful; The Politics of Orgasm. At the skateboard park, a friend brags that he fucked his girlfriend so hard, she came three times. Jamie asks how he stimulated her clitoris. When his friend responds "With my dick", Jamie tells him women need direct clitoral stimulation, with fingers or a vibrator, and she probably faked her orgasm. The boy notices Jamie's TALKING HEADS shirt and says they're a bunch of art fags. He tells them the Talking Heads' drummer is dating the girl in the Talking Heads. He asks if his name is Jamie and they begin to fight.
At home, Dorothea is treating Jamie's wounds from the scuffle. She asks what the fight was about and he says clitoral stimulation; he wants to be a good guy and satisfy a woman one day. Outside Dorothea finds ART FAG spray painted onto one side of her car. On the other side is BLACK FLAG. Jamie knows it was his friend because he called him an art fag. Abbie explains that Black Flag is a hardcore band and their fans don't like the Talking Heads.
In Abbie's room, she suggests that Jamie just let guys believe in their sex stories rather than contradict them. Abbie tells him that whatever he thinks his life is going to be like, it's not going to be anything like that. He asks Abbie to take him to the club.
Abbie takes Jamie to the same club she went with Dorothea. Abbie gives him advice on how to pick up a girl, practicing on Trish (Alia Shawkat), her punk friend. The three of them all dance to the music. Back at home, Dorothea and William talk. He asks her about Jamie's dad. Dorothea tells him that he was left-handed and since she was right-handed, they could do the stock reports together in the morning with him scratching her back with his right hand and writing with his left. William asks if she ever meditates. He then leads her through a meditation process up in his room. She asks how he became the man he is. We see his life in a montage as he explains he used to work in his dad's repair shop and met a woman named Theresa six years earlier. They were in love and moved to a commune in nearby Sebastopol. He didn't really enjoy it but didn't want to lose her. She eventually found him uptight and possessive and left him. Now he doesn't care what the women he dates look like; he just doesn't want to be lonely after losing Theresa. Now he likes making bowls; he gives one to Dorothea.
Outside, William presents Dorothea with a 1939 Ford that he fixed up for her. The two take a ride and end up at a bar. They slow dance. Meanwhile, Jamie, Trish, and Abbie dance to David Bowie. Afterwards, they hang out near Bandshell Park. Abbie tells Jamie he's in love with Julie and shouldn't let her push him around.
Dorothea and William go back to the house and up to Abbie's room. They play her Black Flag record. Neither of them can understand the appeal of the hardcore punk music. Next, they listen to Talking Heads which they like more Dorothea suggests they're more art fag types.
Later that night, Abbie returns home and tells Dorothea that she gave Jamie a beer, taught him how to seduce women and that he eventually kissed Trish. Dorothea is sad that Abbie gets to see Jamie out in the world as a person but Dorothea never will. Abbie's response is to hand Dorothea a Polaroid she took of Jamie having fun.
In his room, Jamie and Julie read through Forever by Judy Blume. He asks what an orgasm is like. Julie tells him she never has them. He asks why she has sex at all. She replies she likes the way men look at her and the little panting sounds they make and their bodies. She tells Jamie half the time she regrets it. He asks why she does it. She points out half the time she doesn't regret it.
Jamie reads from 'It Hurts to Be Alive and Obsolete: The Aging Woman', quoting the author when she says she fears she won't marry again; that, while she is more attractive than her ex-husband, she is sexually and socially obsolete and he is not. She is afraid to show a man she finds him attractive for fear of insulting him. Dorothea hears this and asks if Jamie thinks that's applicable to her. Her feelings are hurt. The next time she sees Abbie, she thanks her for her help but suggests shes gone too far with the women's movement books. When Abbie protests, Dorothea points out she isn't really trained to educate a teenage boy.
In the dining room, all five characters and some handymen watch Jimmy Carters Crisis of Confidence speech, about how owning and consuming things doesn't satisfy us and the road towards self-interest is a mistaken idea of freedom. The men think the speech has doomed him during re-election but Dorothea thinks it was a beautiful speech.
Everyone sits at the kitchen table but Abbie is not participating in the conversation, seemingly in distress. She declares that she's menstruating which offends everyone. Abbie tells Jamie that, to have an adult relationship with a woman, he needs to be comfortable with her having her period. She gets him to say menstruation and then encourages everyone else to say it. William throws his advice in, telling Jamie that sex during menstruation can be pleasurable for the woman and that Jamie should never have sex with a vagina but always with the whole woman. Abbie tells him this is slightly off-topic. Julie says she had her first period while watching One Flew Over the Cuckoos Nest and she never saw the end because she had to rush off to get tampons; William replies by summarizing the ending. Dorothea suggests talking about something else. Julie says she lost her virginity at 14 to a guy she didn't know well; he only used spit for lubrication and she got home in time for curfew and the carpet in his van smelled like bong water.
When Dorothea is alone with Jamie again, she says she'd like to know whats going on with him. He tells her he's dealing with everything and she's dealing with nothing. Upstairs, Jamie reveals to Julie that he's angry at her for revealing what she did at dinner, worried people will think she's a slut. Julie apologizes and suggests the two of them take the car and go up the coast.
Dorothea learns the next day that Julie and Jamie took the car (spray painted with Art Fag) up the 101 freeway. The two of them stopped by a liquor store and got a man to buy them some wine coolers. While driving around, Dorothea is pulled over for changing lanes in the intersection. When the officer asks for her license, she asks, "What if I don't have it?" He asks for her name, address, and date of birth and she says those are personal questions and asks for his name and address.
Jamie and Julie undress in a motel but she tells him she's afraid they're too close for her to have sex with him. He tries to convince her otherwise but she says he is coming off like all the other guys she knows. Jamie puts his clothes back on and leaves, hurt and angry.
Abbie finds Dorothea in the police station, having been arrested after not complying with the police officer that pulled her over. The next morning, Julie calls Dorothea and tells her she's in San Luis Obispo and Jamie left and she cant find him. Dorothea asks Abbie and William to accompany her as she goes up north.
When Dorothea gets to the motel, Julie reveals that Jamie had just been sitting alone nearby the whole time. Dorothea goes to talk to him and he tells her that he was offended that she asked others to guide him because it seemed like she couldn't deal with him anymore. She says she just didn't have faith she could make him happy by herself. Jamie tells her he thought they were fine.
In the motel room, everyone dances to old-time music. Abbie, Julie, and William leave in the 1939 Ford. Jamie and Dorothea stay behind in San Luis Obispo to spend some time together. On his request, Dorothea helps Jamie bleach his hair. He asks her if she's lonely and she tells him she wants to marry Humphrey Bogart in her next life. When he points out Bogart's dead, she points out that she said the next life.
Jamie tells us, in narration, that he thought this was the beginning of a new relationship with Dorothea but it ended up being a one-time thing. Dorothea tells us that in March of 1999, she learns that the cancer in her lungs has travelled to her breast and brain.
Now we hear updates on everyone through their own narration. Julie tells us that she goes to NYU and loses touch with Jamie and Dorothea. She falls in love with a man and moves to Paris and they choose not to have children.
Abbie tells us she will stay In Santa Barbara and a month after she gets married, her female bird dies, followed by the male bird. She creates art in her garage and shows it in local galleries. She ends up having two boys despite her doctor's concerns that she wouldn't be able to carry a baby to full term.
William tells us he lives with Dorothea for another year and then opens a pottery store in Arizona. He marries a singer-songwriter but divorces her after a year. Then he marries another woman and continues to do his pottery.
Jamie tells us his mom meets a man in 1983 who she is in a relationship with until she dies, 16 years later. Every year, on her birthday, he buys her a trip on her biplane (since, in the beginning, we learn she always wanted to be an Air Force pilot). We see Dorothea flying the plane over the ocean as Jamie tells us that years after his mom dies, he gets married and has a son. When he tries to explain what his grandmother was like, he finds it impossible.