It screws with your head. You see the dark side of each person, and the ugly truth of herd mentality and bullying which results from it. There are many subtle under-currents, about right or wrong and about the notion of fairness and justice. At many points I even questioned the typical definition of madness and how tweaking it even a little bit means that violent masses of people doing mindless crimes are more unhinged that solitary occupants of mental hospital cells. 
 There are layers to the story: what is happening the story, what is happening with each character, and about social commentary and personal narratives. All the layers are woven together well. 
 An enthralling read.