Hilary Swank
Before Buffy the Vampire Slayer became a hit TV series, it was a 1992 film written by Joss Whedon—starring none other than 16-year-old Hilary Swank as Kimberly Hannah. "I was completely nervous because I didn't want to mess up," Swank said. "I'd all of the sudden got this opportunity to live my dream. I was living the high life, working in the day and working in the night." She credits the film's director, Fran Rubel Kuzui, for kickstarting her film career.