During the Prohibition Era in America when alcohol was illegal, there were underground nightclubs and watering holes referred to as “speakeasys“. Old newsreel footage from the period would show well-dressed men and women knocking on a door in a seedy back alley that had a special peep hole built in to it. A pair of menacing looking eyes would then peer back from behind the sliding peep hole to check out the visitors. Once it had been determined that they were not police or other undesirables, the door would swing open to reveal a wild party raging on the other side.