Do you Honestly think that would work if it was this kind of mirror.
It might work if the whole wall in the containment chamber was a giant mirror... but still..
The concept would be ridiculously ugly, you are trying to dynamically shape a 2d object in a 3d world.
This is obviously not ideal as it would have impact on performance while not equally looking good to make up for it...
EDIT: if you are going to do that you might as well just clone the fucking all objects and put it on the opposite side of the mirror, linking all objects that move to eachother. Making the mirror a transparent material. This would be the solution as opposed to that other shitty way.