Meryl Streep's last experience of method acting left her "so depressed"

She told Entertainment Weekly: “It was horrible! I was [miserable] in my trailer. I could hear them all rocking and laughing. I was so depressed! I said, ‘Well, it’s the price you pay for being boss!'

"That’s the last time I ever attempted a Method thing!"

As well as drawing on the advice of her old drama teacher, Meryl's portrayal of the tough fashion guru was also inspired by actor-turned-director Clint Eastwood.

She explained: "It was a direct steal from the way I saw Clint Eastwood run a set. He's someone that guys really respect, and he never raises his voice, ever; the one time that he did, it so terrified people for two weeks, they were traumatised.

"In drama school [a teacher] said, 'How you play a king has nothing to do with you - you're just you - it's how everybody else in the room acts when you enter it that makes you the king.' It was all up to them to have this reaction. I could just speak and be slightly nastier than I normally am."

Meryl's co-star, Emily Blunt, admitted she could tell the veteran actress wasn't having a great time on set.

She said: "Meryl is so gregarious and fun as hell, in some ways it wasn’t the most fun for her having to remove herself. It wasn’t like she was unapproachable; You could go up to her and say, ‘Oh my God, the funniest thing just happened,’ and she’d listen, but I don’t know if it was the most fun for her to be on set being that way."