A Sub Trope of Literal Metaphor. It started as nothing more than a simple simile in the real world to describe a look of utter shock, surprise, and/or fright. But at some point, no one knows quite when and no one knows quite where, some genius realized characters in fiction who really have seen a ghost would... look like they've just seen a ghost. Ergo, when characters enter screaming and running [...] [tvtropes.org]