A robot can do everything you admire and love, but a robot can not understand your feelings deeply and it has no any sense to being human. It is so disgusting see those humans that behave like robots as if they can love, but deep inside they lie to their faiths. (Hadas Moosazadeh)
Just untrustworthy persons can be invisible, not because of their willingness seemingly to be confidential, but because of their fear to be identified. A reliable person wouldn't disappear and wouldn't be invisible. To be invisible is a feature and principle of spies, otherwise, you cannot put on them the stamp of spies.