Psychopathy is among the most difficult disorders to spot. The psychopath can appear normal, even charming. Underneath, they lack conscience and empathy, making them manipulative, volatile and often (but by no means always) criminal. They are an object of popular fascination and clinical anguish: psychopathy is largely impervious to treatment.
It is important to note that the vast majority of people with antisocial tendencies are not psychopaths.