Actress January Jones attends the opening of the ZIMMERMANN Melrose Place Flagship Store hosted by Nicky and Simone Zimmermann on July 29, 2015 in Los Angeles, California.
Credit: Donato Sardella/Getty Images

Mad Men alum January Jones headed into L.A.’s Melrose Place last night to help cut the ribbon that wrapped around Zimmermann’s freshly minted California flagship store. And though we always expect the actress to arrive in something stunning, Jones ditched the demure looks we became accustomed to seeing her wear on the show for a summer-cool black and white polka dotted dress from, appropriately, the brand’s youthful collection. It was the daring sheer top half, however, that really caught our eye.

So what’s the secret to trying the peekaboo trend without falling into the fashion victim category? “Wear a nice bra,” Jones told InStyle. “If I had smaller [breasts] I would wear one. I always love watching the fashion shows. Realistically if I was going to go to an award show, I’d have to have stuff lined. Just for modesty—and my grandparents. But I don’t mind it. I don’t mind it at all.” The style-obsessed beauty also knows a thing or two about choosing the right shade of lipstick: "Nars Red Square ($26, is my favorite. It’s like an orangey-red and I wear it a lot. I like this color a lot.” And so do we.

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