What makes us good or evil? It’s a simple but deeply unsettling question. One that scientists are now starting to answer.
Horizon meets the researchers who have studied some of the most terrifying people behind bars – psychopathic killers.
But there was a shock in store for one of these scientists, Professor Jim Fallon, when he discovered that he had the profile of a psychopath. And the reason he didn’t turn out to be a killer holds important lessons for all of us.