OK, so the title might be a big statement. I haven't seen all documentaries ever made and I bet a lot of people will disagree with me.
Note, I never said this was the BEST documentary. But in its simplicity, there is something incredibly interesting and also quite groundbreaking. And here is why:
Sam Vaknin is a self-declared expert on Narcissistic personality disorder and is perhaps most famous for the book "Malignant self-love" which he wrote together with his wife Lydia. Successful businessman turned eco-criminal, Sam is now a doctor of psychology who suffers from all 10 traits of Narcissistic Personality disorder as well as psychopathic traits. Another man who had all 10 traits was Brian Blackwell, who beat both of his parents to death just to cover up the lies he'd told his girlfriend.
In other words, if all this is true, Sam is a very dangerous man.
Ian Walker follows Sam as he undergoes tests that will confirm whether he is indeed a psychopath or not. As the film goes on we get to follow both Sam and the tests he takes as well as Ian himself, describing his relationship with his subject. Ian also interviews Lydia, Sam's wife. As the testing process becomes more in-depth, the story of their journey becomes more complex and in the end they paint a very insightful portrait of what being a psychopath really means.
Though it might be a quite scary revelation, this movie asks some very interesting questions:
Can a psychopath ever be self aware?
If so, can that person control their behavior?
And if we can teach a psychopath to control their behavior before they do something dangerous, what would that mean for society?
And for those who say that this is just one person basking in his own glory - that's exactly what it is. And that's why it is so interesting.