Only diegetic sound in the beginning, the main character walking, opening the door, the jangling of her apartment keys, the noises coming from her laptop, her sitting down, her placing certain objects down on the table for example, her smoking her cig, her phone ringing and the voicemail that follows, and the cars driving and honking on the street outside (which indicates that that the character lives in a big city). Non-diegetic music that gives hints of rising tension begins in the scene when the character sees a shadow behind her via the camera on her laptop. However, it experiences an abrupt end when the main character goes to open the door to confront the person who's knocking loudly on her door, to find no one there. We see some asynchronous diegetic sounds further into the film such as constant knocking on the door, while the main character is within camera view. Both the characters sport different costumes and looks. The 1st character she's seen with more urban street...