Kent Millard writes:
The idea behind this short came while I was waiting to cross a busy intersection in New York City and I noticed that everyone on the other side of the street was facing me. From the expressions on their faces, none of them seemed to be paying much attention to their surroundings; each of them appeared to be caught up in their own lives.
I've always been intrigued by the various personas that we adopt in different settings: how we act at home, is different from how we act at work, or how we act with friends, etc. With all the different "masks" that we put on throughout the day, this begs the question of who we are. For me, what I saw that day was a rare glimpse of how people look when they're not wearing a mask; I found it even more intriguing that this unmasking would occur in such public spaces.
The rest of his explanation is here. And now the video: