Sienna Miller in Christopher Kane at the premiere of High-Rise at the Tribeca Film Festival in New York, New York, April 2016. Photo by Getty Images.
Sienna Miller in Christopher Kane at the premiere of High-Rise at the Tribeca Film Festival in New York, New York, April 2016. Photo by Getty Images.

Who: Sienna Miller.

When: Wednesday, April 20.

Where: The Tribeca Film Festival premiere of High-Rise in New York.

What: A rust-colored cutout Christopher Kane Fall 2016 dress with a few strategically placed charms.

Why: The Tribeca Film Festival red carpet has been filled with looks like this, that gently tread the line between true formalwear and something that doesn't take itself quite so seriously. Here, Miller nails that dichotomy — the deep red tone wouldn't be out of place at a more formal affair, while the safety pinned charms that line one side of the neckline (spelling out K-A-N-E) and dot the dress's skirt, as well as the cutouts on the front and sides, play with a boho-chic aesthetic. It's total London cool girl, which is basically what we'd expect from Miller.

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