mystery

It's almost 11:30pm and I was dead asleep. Someone knocked at the front door. Even the dog woke up and he doesn't wake up for much after ten.

However, I am now very confused because not only was there no one at the door, but the motion detection lights were not on and all the neighboring houses were also dark. There is only one possible way for someone to get to the front door without triggering motion lights and no one was there. Believe me I went to check. There weren't even giggling kids anywhere around the street--the night is cold and clear enough to be able to hear them anywhere around.

I thought it might have been a neighbor in an emergency...but no. No one was there.