Have you ever felt like you were being watched? Seriously though, has anyone ever had that feeling? Especially at night when you are alone and it's dark in your room? In that moment have you ever felt like someone was there. Could you see figures in the dark?
Neurologists, for some time now, have been working with apes and setting up robotic equipment which those apes can telekenetically operate.
Say in some far off future, using this discovery, humans can be placed in coma while telekenetically operating an automaton standing alone in a separate room.
Now imagine that not only can those humans remotely operate the automaton but that their entire sense of being is in possession of that automaton.
Now that automaton, being a machine, could also receive sound and image broadcasts like a television.
What you would have is that human conscience believing the world around him/her as 'real' but in reality everything they see in front of them is fabricated and transmitted to a robot which they are (unknowingly) also inhabiting while in a comatose-like state.
For awhile I thought that this was my own discovery but then realized that I had accidentally resurfaced an idea in a game I saw a long time ago and finally made sense of it subconsciously.
In this introduction of the robot character "KOSMOS" Shion is her assigned host operator who possesses and trains for combat through KOSMOS who also receives virtual feeds.
In this instance not only does it sharpen Shion's combat skills but presents possibility that Shion's shared conscience might one day trip KOSMOS into awareness (autonomy).
As for shadows around us and considering the above theory, those shadows may be technicians and mad scientists passing back and forth and around our automaton which we have feint awareness of despite the transmitted world in front of us blocking our vision of that surrounding external reality.