Kiernan Shipka took a new IG mirror selfie and she looks next-level fit in a sheer corset. To stay in killer shape, she works out with a trainer on the reg.

Case in point: actress Kiernan Shipka. The 22-year-old Mad Men alum might just be the Queen of Core because she hit the streets of New York City this week in an outfit that was ~all~ toned abs.

Kiernan Shipka had already established herself as a high-fashion lover by the time "Mad Men" ended in 2015, often wearing couture looks to star-studded events.