Sixteen-year-old Millie Bobby Brown waited a third of her life to star as Enola Holmes in a film.

Speaking with Deadline, Brown said she was itching to do a movie about Enola ever since she discovered the young adult book series The Enola Holmes Mysteries. However, she had to wait until she was old enough to play the role.

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"I read the books with my sister about five years ago," Brown said. "And we kind of looked at each other and I was like, 'I want to play this.' But I was 11, 12 years old, and the character was 16, so I always knew it would be more of a future ambition for me." Until she was old enough to play the role, Brown co-starred in Netfix's Stranger Things, and landed her first movie role, Godzilla: King of the Monsters.  "I was taken aback by the books," she said. "I just wasn’t really focused on making it just yet."

The Enola Holmes Mysteries, written by Nancy Springer, gave famed detective Sherlock Holmes an out-of-canon tween sister who rebels against Victorian social norms. Instead, Enola, who has a brilliant mind like elder brothers Sherlock and Mycroft, becomes a detective. In the film, she seeks to locate her missing mother.

Directed by Fleabag's Harry Bradbeer, Enola Holmes stars Millie Bobby Brown, Sam Claflin, Adeel Akhtar, Fiona Shaw, Frances de la Tour, Louis Partridge, Burn Gorman, Susan Wokoma, with Henry Cavill and Helena Bonham Carter. The film arrives on Netflix Sept. 23.

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