The Glass Box Society

A small colony thrives on the rubble of post-apocalyptic Earth, safe from the harmful conditions outside by the glass-like material that was built around them. From a distance, the civilization would look like a group of people working together to survive.
Look closer, and you'll see the invisible barrier. The one that divides the smiling faces and white picket fences from the asylum, home to hundreds of children that want nothing more than to break the glass.