You are home alone and its sometime after midnight, lets say 2am and you are still up for whatever reason. You are about to get into bed and get some sleep when there is a knock at your door. Whoever is knocking is relentless, thumping on the door endlessly in a consistent pattern. From the knocks they sound like a strong person. They make no attempts to communicate with you other than the knocking. What do you do?
Personally I would grab my trusty knife and call the police, I'm not taking any chances and if its someone who needs help then surely the police can be of more help than I can.