This film adaptation of Caitlin Moran semi-autobiographical 2014 novel How To Build a Girl, about a teen rock critic who learns to grow past her own cosmetically-applied cynicism, is never as wicked, winning and bruisingly comic as it needs to be. But lead actress Beanie Feldstein is all that and more. If you haven’t yet fallen under her spell courtesy of Booksmart, Lady Bird or her singing to Stephen Sondheim during his YouTube-streamed 90th birthday celebration, here’s your chance. She gives wings to this smartass U.K. comedy set in the early 1990s, which starts streaming on May 8th after debuting last year at the Toronto International Film Festival.

Born in Los Angeles (she’s Jonah Hill’s kid sister), Feldstein tries on a working-class Brit accent to play Johanna Korrigan, a 16-year-old teacher’s pet whose goal is getting out of the shabby Wolverhampton projects. That’s where she’s crammed in with four brothers — the babies are twins — plus her overworked mother Angie (Sarah Solemani) and her dad Pat (Paddy Considine), who illegally breeds border collies to support his delusion of rock stardom. In the room she shares with her brother Kris (Laurie Kynaston), Johanna covers the walls with photos of her idols, from Karl Marx and Sigmund Freud to Elizabeth Taylor and Julie Andrews, each of whom talk her through her various traumas about being the fat girl who’s invisible to popular lads.

The animating plot device is an ad Johanna answers to write for D&ME (Disc & Music Echo), a fictional pop-rock rag that’s looking for “hip young gunslingers.” Johanna hardly fits the bill, and she submits a review of the Annie soundtrack that’s roundly mocked by the all-male staff. But the joke’s on them. D&ME takes on Johanna for the hell of it, even sending the office “jailbait” to Dublin to interview balladeer John Kite, sweetly and sharply played by Alfie Allen, a.k.a. Theon Greyjoy on Game of Thrones. Watching Kite in front of a cheering audience, Johanna falls instantly in love with the singer and with rock & roll. The resulting puff piece is jeered back at the magazine. As an editor burned out on imitators tells her, “our job is to napalm the parasites.”

And so begins the transformation of Johanna into Dolly Wilde, the evil queen of music journalism whose takedowns make her something of a celebrity. On Paul Simon: “He looks like a big toe with a face drawn on it.” And: “Eddie Vedder should do another ripoff of Kurt Cobain and just kill himself.” There are scrappy possibilities in the atmospherics of 1990’s British rock-reporting run by posh snobs who measure their worth in snark. Instead, the movie runs on the formula track as Johanna/Dolly indulges in mild sexual experimentation — she kisses a girl and encourages a foot fetishist. Worse, she betrays Kite’s friendship by exposing his private life in print. It’s revenge for his sensibly rejecting her because of the age difference. When her family criticizes the new her, Johanna turns on her dad, mum and brother by saying, “you’re Ringo, you’re Ringo, you’re Ringo.”

It’s funny — as is a lot of this eager-to-please, all-over-the-place movie — thanks to the dry snap of Moran’s dialogue and Feldstein’s exhilarating performance. Up next as Monica Lewinsky in an FX series about the Clinton impeachment, you get the feeling this 26-year-old star can do anything. When Emma Thompson shows up as a publishing guru who offers Johanna the chance to write a regular column about her self-realization, there’s no need. That’s the movie we just watched, and Feldstein makes it irresistible. How to build a girl, indeed.