Hilary Duff flashed a smile for the camera with Josh Peck and Olivia Thirlby at The Wackness premiere during the LA film festival last night. Hilary has a new movie of her own to start working on, she has just signed on to the star-studded cast of Stay Cool. Hilary will play a high school teenager who flirts with an older alumnus, which sounds like it should fit right in with the former teen queen's new mature persona.