Stay Cool, Hilary Duff!

Hilary Duff looks smoking hot walking to and from the set of her new movie, Stay Cool, in Santa Clara, Calif., on Tuesday afternoon.

The 20-year-old actress arrived in a two-toned tube top, short denim shorts and metallic peep-toe flats with bow details. After twenty minutes in wardrobe and makeup, Hil emerged in a blue ruffly dress and Louboutin heels.

In the film, The Duffster portrays Shasta O’Neil, a sexy high school senior who flirts with the author Mark Polish (Henry McCarthy) and invites him to the prom.

10+ pictures inside of Hilary Duff staying cool…