'It was horrible!' Meryl Streep says she was 'so depressed' while portraying fashion editor in The Devil Wears Prada

It is one of her most iconic roles from her unparalleled 45-year film career.

But making The Devil Wears Prada wasn't exactly a walk in the park for Meryl Streep.

The veteran actress shared some surprising revelations to Entertainment Weekly on Monday, ahead of the 15th anniversary of the film.

The three-time Oscar winner, 71, explained that she was in fact 'depressed' playing Miranda Priestly, a.k.a. the titular Devil in the brilliant comedy film that costarred Anne Hathaway, Stanley Tucci and Emily Blunt, the Daily Mail reports.

To help her get into character, the Kramer Vs. Kramer star said she attempted method acting – a practice famously employed by other performers such as Daniel Day Lewis and Dennis Hopper – which had her embody the icy character both on and off camera.

“It was horrible! I was [miserable] in my trailer,' Meryl recollected about staying separate from the other actors. '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!” the star – who is often referred to as the greatest actress of her generation – added.