At age five she was cast as a lead in her first film, NBC's thriller, Trapped Beneath the Earth. Belle began her career with a small role in the film production of the novel A Little Princess starring Liesel Matthews. Her first lead role was in Rip Girls in 2000, a Disney Channel original movie.
She returned to performing after a short break with the lead role in the remake of When A Stranger Calls. Her next role was in the feature film 10,000 BC, directed by Roland Emmerich, a film about prehistoric humans. Belle's next big release was playing the role of Kira Hollis in Push, a sci-fi thriller involving a group of super-powered youths, hiding from a clandestine U.S. government agency.