Continuity mistake: When Michael Douglas puts on his headphones to listen to the tape in his den, he puts the headphone with the cord on his left ear. When his wife startles him the cord is on his right ear.
Audio problem: There's no doorbell or buzzer sound when Michael Douglas presses the button on Alex's door. (01:41:20)
Answer: So her parents (especially her father) would go through hell, not knowing where she was or if she was safe.
Brian Katcher