"The Favorite" premieres at the London Film Festival

Emma Stone's co-stars in the new period drama "The Favourite" were blown away by her "flawless" British accent.

Actress Emma Stone poses for photographers upon arrival at the premiere of the film 'The Favourite' in London during the London Film Festival, Thursday, Oct. 18, 2018. [Photo：AP]

Rachel Weisz spoke on Thursday at the film's London Film Festival premiere, joined by Stone, Olivia Colman and director Yorgos Lanthimos.

"On the very first day that I met her at the read through, where you read the entire script out, her accent was flawless, I mean, she worked on it before getting there so she didn't need my help or anyone's help."

It was early 2017 and Stone had just won the best actress Oscar for her role in "La La Land." Although it seemed to her castmates that the accent came naturally, Stone said nailing it involved a lot of dialect coaching and a lot of great Brits on set that kept her in line.

A royal romp through the 18th-century court of Queen Anne, "The Favourite" stars Stone and Weisz as Abigail, Baroness Masham and Sarah, Duchess of Marlborough – two cousins plotting against one another to win the favor of the capricious monarch (Colman).

The movie is already generating Oscar buzz after a positive reception from critics and a Best Actress win for Olivia Colman at the Venice Film Festival last month.

"The Favourite" romps into U.S. theaters November 23, and then around the world in early 2019.