Beanie Feldstein worked in a gift shop for nearly a month to master a distinctive Black Country accent.

The 26-year-old actress spent a month living in Wolverhampton, the setting of her movie ‘How to Build a Girl’ – which is loosely based on Caitlin Moran’s memoir – in order to master the dialect and conceal her own Californian tones.

Director Coky Giedroyc said: “We cast her and then we got her a job in Wolverhampton for three weeks, in a gift shop.

"And I lived with her in a flat, in Wolverhampton, for a month.

"She had a dialect coach the whole time.

"She went into this gift shop in the middle of Wolverhampton on the first day, really scared! She wasn't allowed to speak in Californian. So that's how we did it."

Beanie had caught the attention of producers when they saw her performance in ‘Lady Bird’ but they were apprehensive about casting her because she’s American.

However, the actress insisted mastering the accent would be difficult for almost anyone, whether they were British or not.

Coky said: "The only box she didn't tick was the accent. So we immediately Skyped and the first thing I said to her was, 'Bean, how are you going to take this on? It's a big journey.

"And she said very calmly, 'Unless they come from Wolverhampton, any actress is going to have to do this? So why shouldn't it be me?’ “

The team working on the film had initially planned to cast a local actress before broadening their search and eventually settling on Beanie.

Coky said: "We started in Wolverhampton and took the net wider and wider.

"We broadened it to the Midlands, and then it was the North, and then it was the UK.

“And then Alison (Owen, producer) was watching 'Lady Bird' and she rang and said, 'We've found her, this is it.'

"I immediately went to a screening of it and she just lights up the screen. She's a movie star.

"So suddenly, there she was, this luminous, very talented person who actually ticked all our boxes."