Short-story writer David Sumner is woken at dead of night by the phone ringing, and hears his daughter's voice saying, slowly, deliberately, almost gravely, 'This is important. I did not call the police. It was your family that called the police.' Then she hung up.
At length he finds that it is not his daughter after all, but his mind is still in shock, and full of questions: Who made the call? Who was the call meant for? Who called the police, and why?
His wife challenges him to make use of the experience by turning it into a novel, with each chapter depicting one of the possible scenarios which might have led to the call in the night. When he eventually finds out the real circumstances of the call, that will be his final chapter, and his mind will be at peace again.