When the planets align just so, actress Tilda Swinton deems us earthlings worthy of her appearance on the red carpet. For her latest effort, the Marvel film Doctor Strange, Swinton's on-screen character aligns perfectly with her public persona: She plays The Ancient One, a mysterious Celtic mystic and something of a spirit guide-slash-teacher to Benedict Cumberbatch's titular Doctor Strange, a surgeon who loses function in his hands after a car accident. So, of course, she's turned to her red carpet bestie, Colombian designer Haider Ackermann, now of Berluti, to provide the slightly surreal, slightly futuristic wardrobe for another press tour. Her well-dressed co-stars put up their best fights for the spotlight — Rachel McAdams in a lavender Atelier Versace gown; Benedict Cumberbatch in a navy velvet suit jacket — but there's no competing with Swinton when she gets into some iridescent chartreuse.

Tilda Swinton in Haider Ackermann at the U.S. premiere of Doctor Strange in Hollywood, California, October 2016.
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Who: Tilda Swinton.

When: Thursday, October 20.

Where: The American premiere of Doctor Strange in Hollywood, California.

What: A custom pleated chartreuse Haider Ackermann Spring 2017 gown with a gold belt.

Why: Though her personal style often tends towards androgynous ensembles, Swinton is no less able to pull off a full-length gown situation. With narrow pleats and strong shoulders, the gown gives her the powerful look of an empress descended from another planet; her teased platinum hair with a few strategic flyaways is a kind of crown topping off the look. Plus, as always, Swinton has the attitude to pull off the look: She poses, leaning ever so slightly to the side, with pursed lips and a faintly amused expression. A strong fuchsia lip provides a sharp contrast with the harsh tone of the dress. No mortal has a right to be able to pull off this color, which is perhaps the best evidence yet that Swinton isn't exactly mortal.

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