Hayden Panettiere is a Happy Hero

Hayden Panettiere flashes her pearly whites as she films a scene for NBC’s hit series Heroes in Los Angeles on Wednesday afternoon (September 2).

The 20-year-old actress, who just celebrated her birthday late last month, was also spotted out yesterday afternoon (September 4) with her pup before stopping at a nail salon in Santa Monica, Calif.

This season on Heroes, Hayden gets a new friend in Madeline Zima (you may remember her from A Cinderella Story with Hilary Duff). Madeline will play Gretchen, Claire’s new friend and college roommate.

10+ pics inside of Hayden Panettiere…