Margot Robbie's Plunging Dress at the Once Upon a Time in Hollywood Premiere Made Us Forget About Old Hollywood

[MUSIC] Hi boys, Harley Quinn, how you doing? What was that? I should kill everyone and escape? Sorry, the voices. This is how it's gonna go. I'm gonna take custody of the kids. If you agree to the divorce right now, I will allow visitation. Okay? Don't try to fight it. It'll save us both a lot of money, and I got a feeling you're gonna need it. [MUSIC] [MUSIC] [MUSIC] [MUSIC]

Not to be outdone by her co-stars, Margot Robbie outshone Brad Pitt and Leonardo DiCaprio at the London premiere of Once Upon a Time in Hollywood. While the duo looked perfectly dapper in their black suits, Robbie managed to coordinate with the event's sunset hues. Her plunging, warm orange Oscar de la Renta gown was a perfect match to the carpet and backdrops, but her choice to eschew red carpet standbys like fit-and-flare gowns and naked dresses made the choice a real standout.

According to E! Online, Robbie paired the flowing dress with a gold box clutch and matching Tabitha Simmons heels. Her relaxes wavy hair was the perfect way to show off the dress's flowing lines, which included a halter tie that blew in the London breeze and draped panels in addition to the showstopping deep-V neckline.

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Robbie kept her jewelry to a minimum, which is a turn from her experience making the movie. People reports that Robbie got to wear Sharon Tate's jewelry during the filming of Once Upon a Time in Hollywood. Sharon's sister, Debra, offered the jewelry for Robbie to get into her role, an experience the actor described as both sad and happy

"It was kind of sometimes very sad to be that closely connected with real-life Sharon," Robbie said. "Suddenly the tragedy of it all would hit you and you'd be tremendously sad." She added that being able to feel an actual connection to Sharon was a totally different experience and explained that it made her "feel so happy" to be able to connect with someone so deeply.

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"It was immensely important for me to honor Sharon's generous spirit," she shared. "I felt an enormous sense of responsibility. She really was such a beautiful character to play."

The jewels aren't the only homage to Sharon Tate that Robbie's shown. During the movie's premiere at the Cannes Film Festival back in May, Robbie wore her hair in Sharon Tate's signature braids.