British actress Keira Knightley rose to prominence in the 2000s, but hit all-new heights when she appeared in the 2005 adaptation of Jane Austen’s Pride and Prejudice. Not even two years later, she appeared in another adaptation of a book: Atonement. Knightley had made her mark appearing in the Pirates of the Caribbean franchise as Elizabeth Swann, but before then she was only decently known in the United Kingdom for some of her previous roles. She catapulted even more into international stardom with Atonement and Pride and Prejudice and quickly became known for her romantic period dramas, something only furthered when she appeared in the 2012 adaptation of Anna Karenina.

While Knightley has had a prolific career so far, there is something she has become known for in her movies: the clothes she’s dressed in. Whether on Pinterest or Tumblr, the public has absolutely loved some of the costume design that appears in Knightley’s films, thus making her an accidental icon and trendsetter in fashion and lifestyle. These are some of her best costumes in movies so far.

4 Atonement — The Fountain Scene

Woman stands in floral blouse while holding flowers.
Relativity Media

In Atonement, the fountain scene where Robbie and Celia fight over the vase is pivotal, as it plants the seed in young Briony’s mind that something bad is going on between them. There is also something special about this scene: its usage of costume on Knightley. She is, in the first moments, wearing a floral blouse and blocked skirt, mixing patterns along a more subdued color palette. This is not common for the 1930s, when this movie is set, as it would be rare to mix two louder patterns like the ones on her blouse and skirt. It is during this scene, too, that Celia jumps into the fountain to retrieve the parts of the vase that had sunken to the bottom, leaving her in nude undergarments in front of her love interest. It is then, at that moment, that Celia is depicted as a woman, not a girl.

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3 Anna Karenina — The Black Ballgown

Woman stands in ballroom wearing black gown.
Working Title Films

Anna Karenina is considered one of Tolstoy’s masterpieces and a crown jewel of Russian literature, so while the 2012 movie adaptation may not be the best representation of what the book has to offer, it still manages to be visually captivating. As many of its characters are aristocrats and have some of the wealthiest individuals that Russian society can offer, it is no surprise that the costumes are opulent. The black ballgown that Knightley wears in one significant scene is just one example of many: it is a work of art. Many of the costumes are not historically accurate in this film, and this is one of them. As per the New York Times, the costume designer was inspired by 1950s haute couture, specifically Balenciaga and Dior, to create the bodice and utilized Chanel jewelry to accessorize the character.

2 Pirates of the Caribbean: At the World's End — Pirate King

Female pirate stands on edge of ship, holding the ropes.
Walt Disney Pictures

Elizabeth Swann, Knightley’s character in the Pirates of the Caribbean franchise, has had many big moments when it comes to fashion, but her wardrobe in At the World’s End takes home the award for her best fashion moments in the series. She wears a long black coat with gold embroidered trimming, which may not be the ideal garment to wear in a tropical setting, but certainly makes her look like someone in charge. Complete with a corset, adding a more feminine touch to a largely masculine outfit, everything about her attire establishes who she is, what her ranking is on the pirate hierarchy, and that she is not someone you should be casually messing with right now. It is a fitting transformation to complete her character arc throughout the series. She is no longer an aristocrat, but belongs to the realm of piracy and has accepted that part of her.

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1 Atonement — The Green Dress

James McAvoy and Keira Knightley sit at the dining table in Atonement
Universal Pictures

Knightley’s green dress from Atonement is one of her most iconic looks so far in the movie world. It may even be one of the most iconic looks in a period film. In 1930s England, a dress like this would be uncommon, so it would not be exactly accurate to the period. Silk, plunging backs, and evening gowns were commonplace for 1930s attire in England, but thinner straps and a plunging neckline would not be considered acceptable during that period. So while the dress may not be historically accurate for the period it is trying to represent, it still looks beautiful and seductive on the screen. It serves as an indicator for the viewer, as well as Robbie, that Celia is no longer a child-like Briony and thus can be seen as a full-fledged woman—or an object of desire—compared to some of her previous scenes.