Amal Clooney is the definition of chic at Prince Charles' swanky event

If you're going to look like royalty, it may as well be for an event celebrating a charity called The Prince's Trust.

Amal Clooney joined husband George Clooney at the event hosted by Prince Charles Tuesday in Buckingham Palace. She also got a group photo with other guests, actors Chiwetel Ejiofor, Luke Evans, Tamsin Egerton, Josh Hartnett and Benedict Cumberbatch.

The human rights attorney was the picture of sheer elegance in a white gown with lovely draping up top, a metallic box-shaped clutch and, wait, is that … no it couldn't be. Yes, but it is: An asymmetrical cape.

Remember this date, fashionistas. Because March 12 could be the day that the one-armed cape trend began, before thousands of women across the world shook hands with a chic bat wing.