By Kallie Gregg

Staff Writer

Christine McPherson (Saoirse Ronan) spends much of writer/director Greta Gerwig’s delightful “Lady Bird” trying to break away from the conventions of her life — the name her parents gave her, the town where she’s grown up, and the routine of her life at a private Catholic high school in Sacramento, California.

Christine has recently christened herself “Lady Bird” (“Is that your given name?” she’s asked, to which she responds, “I gave it to myself. It was given to me by me.”) and she’s determined to live up to the glamorous quirkiness of her new identity.

She wants to go to college on the east coast, “where there’s culture,” but is unlikely to be accepted to her schools of choice. She wants to be an actress, but she’s only cast in the chorus of the school play. She falls deeply in love, but cannot help herself from checking out the cute guitarist in a local band while she and her boyfriend hold hands.

All of these maddening adolescent contradictions coalesce during Lady Bird’s senior year. The highs and lows are of equal ferocity and similar frequency, flipping between the two rapidly.

In one moment, she and her mother Marion (Laurie Metcalf) argue in a thrift store while searching for a dress for Lady Bird to wear to Thanksgiving with her new boyfriend’s family. Mid-sentence, as she’s trading a verbal barb, Marion produces a dress. “Do you love it?” she asks. “It’s perfect,” Lady Bird exclaims.

Moments like these encapsulate the feel of the film — at once righteously funny and heartrending, every scene vital and fully realized.

Although the plot of “Lady Bird” treads familiar territory, Gerwig’s affectionate treatment of the subject matter, setting, and characters envelop the entire runtime in bold, refreshing tenderness. Ronan’s performance is a remarkable achievement, her embodiment of the character spectacular to behold.

As Lady Bird applies to college and crafts her admissions essay, one of her teachers, Sister Sarah, remarks that she writes about Sacramento with “such care.” Lady Bird is taken aback — she’s spent the last 90 minutes establishing how desperate she is to escape the place. “I guess I pay attention,” she concedes. “Aren’t they the same? Love, and attention?” Sister Sarah asks.

This, at its heart, is “Lady Bird’s” thesis. Ronan’s acting is surrounded by places and people crafted with an equal amount of care and agency, both by Gerwig’s writing and her costars’ performances. The world of Sacramento circa 2002 and Lady Bird’s place in it come alive vividly — given attention, given love, the result is a rare combination of truth and beauty.