The Diary of a Teenage Girl is a American comedy-drama film written and directed by Marielle Heller , based on the hybrid novel of the same name by Phoebe Gloeckner. It stars Bel Powley as a year-old girl who becomes sexually active by starting a relationship with her mother's boyfriend. In San Francisco, year-old aspiring cartoonist Minnie Goetze begins keeping an audio diary. She is stirred by her awakening sexuality and wants to lose her virginity.
She fears she may be unattractive. When Minnie's bohemian mother Charlotte is too busy to go out with her boyfriend Monroe, she suggests he take Minnie out instead. At a bar, they flirt and she tells him she wants to sleep with him.
They begin meeting at his apartment and having sex. She shares the details of her sexual experiences with her friend Kimmie, and records them in her audio diary. At a comic book store, Minnie sees cartoonist Aline Kominsky signing books. She mails Aline her first comic, about a woman walking through town. Minnie sleeps twice with her schoolmate Ricky, but he finds her sexual enthusiasm intimidating.
At a bar, Minnie and Kimmie decide to pose as prostitutes. They fellate two boys in the bathroom, but the next day they agree it was a bad choice. Minnie's stepfather, Pascal, calls from New York City and invites Minnie to live with him, but she declines.
Charlotte loses her job as a librarian, so Minnie and her younger sister Gretel ask Pascal for money, and though he is irritated, he sends the family a check.
