Hailey worked with stylist Maeve Reilly on the custom look from the brand, which was complete with Cartier jewels and towering Jimmy Choo sandals that Hailey showed off when she worked her LBD from the side, the front, and, well, mostly the back. Read on to see the supermodel completely own an understated piece that had everyone buzzing (despite the number of floor-sweeping dresses at the event), then shop all the similar versions you can pick up ahead of your next holiday party. Your fellow guests won't even know what hit them.