The phrase "When a Stranger Calls" refers primarily to a horror film originally released in 1979. It was directed by Fred Walton and tells the story of a babysitter terrorized by psychopathic prank phone calls, only to find out that the calls are coming from inside the house. The film became a cult classic, especially noted for its chilling opening sequence. There was also a remake titled "When a Stranger Calls" released in 2006, directed by Simon West. This version expands the original short opening of the 1979 film into a full-length psychological horror movie. It follows a teenage babysitter named Jill Johnson who receives increasingly threatening phone calls from an unidentified stranger while watching children in a remote home. Both versions revolve around the central theme of a babysitter receiving calls from a stranger, which leads to a night of terror and suspense. The story is based on the urban legend "The Babysitter and the Man Upstairs".