Twenty-two-year-old Dianna Agron hasn't been acting for very long, but she has already has a handful of hit television show appearances under her belt, most notably on "Heroes" and "Veronica Mars." Agron plays in "Glee" a Cheerio (that's cheerleader in McKinley speak) who's devoutly religious, but is a true mean girl through and through.

Twenty-two-year-old Dianna Agron hasn't been acting for very long, but she has already has a handful of hit television show appearances under her belt, most notably on "Heroes" and "Veronica Mars." Agron plays in "Glee" a Cheerio (that's cheerleader in McKinley speak) who's devoutly religious, but is a true mean girl through and through.