sorry and i do not have much time to write . i be not a psychologist but have know one for 25 year . she say that scott wilson portray a sociopath ( no conscience ) extraordinarily well . i agree . she also say that robert blake portray a person with anger and impulse control who have a conscience but couldn not control himself superbly . i agree . what a chilling and tremendous film . i have see over 2000 film and would rank this in the top 100. my lifelong friend deal with client such a these regularly . my only criticism be the preachy narration at the end of the film . many people grow up in less than ideal circumstance but only one in a million will behave a these 2 loser do .