Noah Baumbach has been making delightful movies about white twentysomething angst for, well, 20 years. He aged up a little bit with this spring’s While We’re Young, which lovingly skewered both its fortysomething leads and the twentysomething “artists” they befriended. The director got a little sweeter with 2012’s Frances Ha, the first movie in which Greta Gerwig served as his star, co-writer and muse.

Mistress America, which Gerwig also co-wrote, is somewhere in the middle. 

Baumbach’s focus is still on a certain kind of semi-youthful, moderately creative narcissism, here embodied by Brooke (Gerwig), a 30-ish New Yorker who becomes a beacon for college freshman Tracy (Lola Kirke). Their parents are getting married in a few months, which gives them a tenuous connection that strengthens as Tracy tags along in Brooke’s madcap life, her admiration like jet fuel for Brooke’s ego.

Tracy travels in Brooke’s wake, eventually swept along on a trip to wealthy Connecticut, where Gerwig flails her way into a farcical climactic scene involving her female nemesis and her ex-boyfriend, along with Tracy, Tracy’s friend Tony (Matthew Shear), Tony’s wickedly jealous girlfriend Nicolette (Jasmine Cephas Jones), a lawyer and Harold (a neighbor played with delicious dryness by Dean Wareham).  

Tracy, a would-be writer, isn’t just there to worship at Brooke’s stylish feet. She knows good material when she sees it and writes her way into a pretentious literary society with a story built from scraps of Brooke’s life. Near the end, the story becomes central in a moral quandary that Baumbach and Gerwig are smart enough not to resolve with a tidy answer. Is it stealing? Does it matter? 

The snippets Tracy reads in voice-over are terrible, as contrived as some of Brooke’s behavior. (Roll them into one character and they’d give Hannah from Girls a run for her money; Mistress America sometimes feels like what Girls dreams of becoming.) But that’s the point: Like most characters in Baumbach’s films, neither woman has figured herself out yet. One just puts on a better front.

Brooke can’t stop reaching for an imaginary hearth (which she isn’t sure is a word) and home; Tracy sees Brooke’s life as something to want. And nobody’s got anything right about anyone else — or themselves. Baumbach’s great skill is in crafting snappy but revealing dialogue; the funniest lines are the ones that say the most about the characters, all of whom are deeply self-centered, yet interested in being kind — if they could only figure out how. (Bijou Art Cinemas)