Image copyright Getty Images Image caption Beanie Feldstein has previously starred in Booksmart and the Oscar-nominated Lady Bird

If you happened to visit a gift shop in Wolverhampton last year, you may well have been served by a Hollywood star when you reached the tills.

That's where US actress Beanie Feldstein spent a few weeks working as she tried to pick up the tricky accent for her new movie How To Build A Girl.

She plays the lead role in the screen adaptation of Caitlin Moran's novel.

"I'm from Los Angeles so the first battle was the Wolverhampton accent," Feldstein explained.

"The West Midlands is a place I know very well and love very much now. For preparation, I went to Wolverhampton for two weeks and I worked in a store, and I had to speak in the accent the entire time I was working.

"And the first week I did not fool anybody!" she laughs. "But then by the end of the second week with a little help from the girls I was working with - they would yell at me when I got something wrong - by the end of the week I felt much more comfortable."

Image copyright Getty Images Image caption Caitlin Moran's novel How To Build A Girl is loosely based on her own career

Feldstein is a rising star in Hollywood having recently appeared in Olivia Wilde's directorial debut Booksmart and the Oscar-nominated Lady Bird.

In How To Build A Girl, which has just premiered at the Toronto Film Festival, she plays a young girl who aspires to be a music journalist.

While Moran's 2014 novel was fictional, the storyline was somewhat autobiographical, and the lead character Johanna Morgan's journey mirrors her own.

Moran grew up the eldest of eight children in a Wolverhampton council house, but at the age of 16 started writing for NME and went on to a distinguished career in journalism (she is now a columnist for The Times).

More from Toronto:

Speaking after the film's premiere, Moran said: "Well first of all, it's much more fun watching it than it was to live through it, I really enjoyed the last 90 minutes in a way that I didn't enjoy the two years the film is set over.

"When I wrote the book, I was just tired of seeing girls who were punished by the world. I love dystopian fiction as much as the next person, but one of the biggest sub genres has been teenage girls who have to save the world literally, rather than just what you should be doing in your teenage years, which is working out which bra looks best, what makes your hair looks best, and getting off with some boys.

"And so adapting it was just writing down a list of things I wanted to see a brilliant girl do on screen, and thankfully we found Beanie."

Image copyright TIFF

The first reviews of the film have been positive, although some critics suggested Feldstein hadn't quite nailed the accent despite her research efforts.

"Feldstein is as charming as ever, delivering her lines with the earnestness and flourish of an extremely theatrical teenage girl. Her British accent, on the other hand, is so-so," wrote Anne Cohen in Refinery29.

But she praised the film's "searing emotional core", adding that it "reminds us that too often, smart, happy girls are beaten down into submission by society and circumstance."

IndieWire's Kate Erbland had a similar take, writing: "Feldstein, despite tripping over the working-class Brit accent required, inhabits the character with ease, and is measured enough to make the differences between Johanna and her previous coming-of-age characters pop."

Feldstein isn't the first US star to grapple with a British regional accent. Anne Hathaway's attempt at a northern accent in One Day famously did not go down well with fans of the original David Nicholls book.

Image copyright Getty Images Image caption Game of Thrones star Alfie Allen plays a rock musician in the film

How To Build A Girl, which is directed by Coky Giedroyc, also stars Game of Thrones star Alfie Allen and Paddy Considine, with guest appearances from Chris O'Dowd and Emma Thompson.

The storyline sees Johanna adopting a pseudonym, Dolly Wilde, and grabs the attention of her peers with her cutting and sardonic writing style.

She begins experimenting sexually and changes her appearance to reflect her new career as an infamous rock journalist.

But Johanna struggle to maintain her rock 'n' roll persona and lifestyle for long, and as she grows she gradually embraces the sweeter and more optimistic girl she is at her core.

"It's not really the story of two girls, it's the story of one girl trying to make herself into another and then coming back," explains Feldstein.

Reflecting on her own youth, Moran said: "When I was a teenage music journalist, being able to write in a national magazine and express my views to a large readership was something not many 16-year-old girls could do.

"Now, because we have the internet and social media, every 16-year-old in the world can go out and give their opinions."

An exact release date for the film has not yet been confirmed, but Lionsgate have already announced they will distribute the movie in the UK.