The Ring (2002)
For most of the film, little Samara is only seen through visions and video recordings. Those alone are enough to freak us out. She sports a pure white dress and long hair that obscures her face, which doesn't sound all that frightening until horrifying visions start awakening in your head, all caused by her. Oh, and don't look into her eyes if she crawls out of your TV, unless you want to contract an acute case of Edvard Munch-face.