A teenager living with her working-class family on a council estate in Wolverhampton, England, grows up to become a popular but conflicted music journalist.
Johanna Morrigan is an aspiring writer, but she is typically awkward and unconfident. When she is hired by a local paper, D&ME, she changes her image as Dolly Wilde to become a hip rock n roll critic. In her work and travels, she meets and befriends musician John Kite, even falling in love with him.
When her publishers want her to be meaner in her writing, Johanna begins to write harsh criticisms of famous rockers, and her new attitude extends to her family. It all culminates with her quitting D&ME after she hears them trash-talking her, but Johanna soon becomes depressed and commits self-harm until she is knocked unconscious by an award statue in her room.
Johanna recovers and her family forgives her. She reverts to her old, kinder ways and is hired by a different paper that appreciates her earnest style of writing. She apologizes to John for writing a bad piece on him, and they resume their friendship.
In the 1990s, 16-year-old Johanna Morrigan lives on a council estate in Wolverhampton with her aspiring rock star father Pat, exhausted mother Angie, and brothers Krissi, Lupin, and infant twins. Johanna dreams of escaping her life to become a writer, and finds comfort in speaking with the portraits of her idols covering her bedroom wall. A poem she wrote is selected for a televised competition, but she is overcome with nerves and humiliates herself on national television. After inadvertently revealing that her family is illegally breeding Border Collies, resulting in her father losing his disability benefits, Johanna is determined to earn money for the family. Krissi refers her to D&ME, a London music paper seeking a rock critic, and Johanna submits a review of the Annie soundtrack. She is invited to interview at the D&ME offices, but arrives to learn the staff assumed her submission was a joke. Undeterred, she convinces them to give her a chance, and is assigned to cover the Manic Street Preachers in Birmingham.
Eager to reinvent herself, Johanna adopts a new style, bright red hair, and the pen name “Dolly Wilde”. She attends her first rock show and falls in love with the music, immersing herself in the local scene. D&ME agrees to send her to Dublin to interview musician John Kite, who is instantly smitten with her bubbly personality. She spends the day with John, who brings her onstage with him. Afterward, they open up to one another about their lives, and Johanna finds herself enamored with him. Returning home, she writes a glowing feature on John, which her editor dismisses as the work of a teenage girl with a crush, and she is fired. Realising that negative criticism is the path to success, Johanna begins writing deliberately cruel reviews as Dolly, and is rehired at D&ME. Now a scathing but popular critic, she is able to support her family with her writing income. She becomes sexually active, forcing Krissi to listen as she recounts her sexual exploits. Pat, still hoping to achieve fame with his band Mayonnaise, gives his single to Johanna to promote. She brings it to a D&ME gathering where it is derided by the others, who force her to skeet shoot the record.
At a music industry event, Johanna receives an award for “Arsehole of the Year”, and runs into John. She drunkenly confesses her feelings for him and tries to kiss him, but he kindly rejects her advances. The next morning, she writes a piece about his life, including deeply personal details he told her in confidence. She quits school, leading her parents and Krissi to confront her over her increasingly delinquent behaviour, but she cruelly reminds them that her money is supporting the family. Johanna goes to a party with her coworkers, where she accepts a full-time position at D&ME, but overhears them badmouthing her. Unleashing a tirade against their smugness and negativity, she quits and returns home to find John has called about her article, ending their friendship. Distraught, Johanna drinks and cuts her wrist with a drawing compass, but is knocked unconscious when her “Arsehole” award falls on her head. Recovering at the hospital, she reconciles with her family.
To make amends, Johanna tries to apologise to every musician she criticised. She writes a piece on self-harm, and is hired by The Face magazine to write her own column, “Building a Girl”. Finding John, Johanna apologises for her article, and shows him her original writing about him. She also gives him her newly cut-off hair as a token of apology. John forgives her, and says that while they may not be in a relationship anytime soon, he is happy to be her friend. Breaking the fourth wall, Johanna tells the audience that a girl can always reinvent herself for the better.
The film opens in the ’90s in Wolverhampton. Johanna Morrigan (Beanie Feldstein) laments that she is never going to find a perfect escape from her life like the heroines in the books she has read. She lives with her aspiring rock star father Pat (Paddy Considine), put-upon mother Angie (Sarah Solemani), and brothers Krissi (Laurie Kynsaston), Lupin (Stellan Powell), and baby twin brothers, plus their dog Bianca. Johanna also keeps a wall full of her favorite figures in history or fiction, like Sylvia Plath (Lucy Punch), Elizabeth Taylor (Lily Allen), Jo March (Sharon Horgan), Sigmund Freud (Michael Sheen), Cleopatra (Jameela Jamil), Maria Von Trapp (Gemma Arterton), the Bronte Sisters (Sue Perkins and Mel Giedroyc), and Karl Marx (Alexei Sayle).
Johanna is also an aspiring writer, which her teachers note but also feel that she ought to ease up and not be such an overachiever. One of her poems has been selected for an upcoming televised competition in Birmingham. She is excited and brings the whole family along. However, when she is picked to read her poem, she gets nervous and starts rambling before going to the host, Alan Wilko Wilkerson (Chris O’Dowd), and comparing the two of them to Shaggy and Scooby-Doo, even talking like a dog. Johanna humiliates herself and her whole family, as the whole school has witnessed the debacle.
The Morrigans experience more financial troubles, with their TV getting repossessed after it’s discovered that Pat was illegally fostering border collies and collecting disability. Seeing how dejected his sister is, Krissi refers Johanna to a local music paper, D&ME, that is looking for critics for rock music. Johanna decides to take on the gig and sets up an interview after submitting a review of the soundtrack to “Annie”. The writers at the paper laugh it off as a joke and dismiss Johanna, but she picks herself up and insists that she be put on for the job. The others come around and agree to let her join, assigning her to a Welsh band.
Feeling that nobody is going to take her seriously as plain old Johanna Morrigan, she dyes her hair bright red and uses the alias Dolly Wilde. With a little help from Pat, Johanna attends her first-ever rock show, coming to quickly fall in love with the genre. She takes in more rock music and gets Krissi to let her into the school’s fan magazine club. Wanting to score an interview with an actual rocker, Johanna begs the publishers, and they agree to send her to Dublin for her first interview.
Johanna flies out and meets musician John Kite (Alfie Allen). They hang out together where Johanna nervously asks him some personal questions, but they eventually sit together and open up to one another about their personal lives, hopes, dreams, and fears. Johanna finds herself in love with John. She writes a piece on him where she praises him, but her bosses don’t like it because it sounds too much like a teenage girl gushing over an artist, so they fire her. However, after learning that they want her to be meaner with her writing, Johanna promises to do so and is rehired.
As Dolly, Johanna starts writing cruel reviews about many famous bands and musicians, which earns her disdain from those people but praise from the others that she works for. She also starts to become more sexually active, even forcing Krissi to listen to her discuss her myriad sexual encounters.
Pat gives Johanna some flyers and copies of his band Mayonnaise’s music. She attends a gathering with the other writers and publishers, where they drink and trash talk some artists before launching their CD’s and shooting them. They find a copy of Mayonnaise, not knowing Johanna’s relation to them, and they make her shoot their CD. She does so but feels as though she has just betrayed her father.
Johanna receives an award for “Arsehole of the Year” for her writing. At the ceremony, she sees John and chats with him, but when she reveals her feelings for him and wants to kiss him, he rejects her advances, saying that it’s not his style. She ends up writing a bad piece on him, and later returns to school with a more delinquent attitude to maintain her “arsehole” persona. Her parents and Krissi confront her recent behavior and lack of support, but she argues that she has been holding the family up lately and been bringing in more money, claiming that she has been carrying them on her back.
Johanna goes with her coworkers to a party, along with one of the publishers she is hooking up with. She is even offered a full-time position at the paper, to which she accepts. However, after a few hours of partying, she overhears them badmouthing her, and she unleashes a tirade upon them for their constant mockery of her, being just a bunch of angry boys, and their overall terrible personalities, and she quits and leaves.
Johanna returns home to her family ignoring her. Angie reads her a message from John where he finally answered all her earlier interview questions, which she sees as she looks at the published bad article that she wrote on him. Feeling depressed and at her lowest point, Johanna drinks and cuts her wrist until she is knocked unconscious by an award statue falling on her head. She is sent to the hospital where she recovers, and her family forgives her for how she treated them.
Johanna gets herself back together and manages to call and apologize to almost every musician and band she trashed. She also writes a piece on self-harm, which is noticed by another local paper. She is interviewed by head publisher Amanda Watson (Emma Thompson), who likes her paper a lot and hires her.
The last thing Johanna decides to do is apologize to John in person. She gives him a copy of Krissi’s magazine, as well as a large lock of her hair as a token of her apology. John forgives her and says that while they may not be in a relationship anytime soon, he is content being her friend. As they are walking away together, Johanna takes a moment to turn to the viewers and say that the best thing a girl can do is to do something big for themselves.