You might know Greta Gerwig as the charming and quirky and delightful actress from films such as “To Rome With Love,” “Frances Ha” and “Jackie,” and what a fine and impressive career she’s made for herself as a performer — but based on her work as the writer-director of “Lady Bird,” this is my request:

Please write and direct another 25 films, Greta Gerwig.

Set in the Sacramento of the early 2000s and inspired by Gerwig’s experiences growing up there, “Lady Bird” has a distinct indie-movie vibe without falling into any typical indie-movie pitfalls. It is smart without being smug, insightful without being condescending, funny without being mean-spirited and genuinely moving.

It’s unique and original and fresh and wonderful, and can you tell I loved it?

Saoirse Ronan (“Atonement,” “Brooklyn”), who is only 23 but is already on the “it’s only a matter of time” Oscar fast track, delivers a pure and honest performance as high school senior Christine McPherson, who has rechristened herself “Lady Bird” because she finds her given name, and her given life, boring.

Lady Bird is a bright but not particularly accomplished student at an all-girls Catholic school. She’s not a total outcast, but she’s not one of the popular kids. She has one truly close friend, Julie (Beanie Feldstein, funny and natural and terrific), who is a step below even Lady Bird’s decidedly average placement in the high school hierarchy.

To our great good fortune, Steppenwolf Theatre legends Laurie Metcalf and Tracy Letts play Lady Bird’s parents.

Lady Bird’s mother Marion works double shifts as a nurse in a psychiatric hospital and clearly loves her family (which includes an adopted son named Miguel, played by Jordan Rodrigues), but wow is Marion rough on her daughter. We can understand why Lady Bird’s secret dream is to get accepted at a college on the East Coast, as far away from Marion as possible.

Lady Bird’s father Larry is a sweet but tragically sad man, trapped under the blanket of clinical depression. Larry has learned to pick and choose his battles and his causes, because he knows he has only so much emotional strength to spend.

There’s no level of acting on a higher plane than what Metcalf and Letts achieve in this film. This is what greatness looks like.

Lucas Hedges (“Manchester by the Sea”) plays Lady Bird’s first serious boyfriend, Danny. When their relationship takes a surprising turn, it’s handled with grace and intelligence, and it feels just right.

Even the beautiful and wealthy and superficial and popular and envied-by-all character (Odeya Rush) is portrayed in a way that transcends the usual high school movie stereotypes. We (and Lady Bird) see her future before she does, and there’s something sad (and authentic) about that.

Gerwig’s screenplay is a treasure trove of pitch-perfect scenes, whether it’s the relatively straightforward, high-school comedy material, or the brutally raw mother-daughter confrontations that will undoubtedly leave emotional bruises on both participants for decades to come.

Lady Bird’s life adventures are just beginning as “Lady Bird” the movie draws to a close.

Perhaps Gerwig will pick up Lady Bird’s story in a follow-up film. Or maybe she’ll say goodbye to these characters and move on to something else.

Either way, I’m sure we will remember this film as the first step in a long and impressive career.

★★★★

A24 presents a film written and directed by Greta Gerwig. Rated R (for language, sexual content, brief graphic nudity and teen partying). Running time: 93 minutes. Opens Friday at local theaters.