A detailed overview of various serial killers throughout the decades, with some interesting insights from criminologists and behaviorists about aspects that they share in common or that distinguish them. The main issue for me is that same interviews are used in many, if not all of the episodes. Consequently, one episode tends to blend with the others. They could have cut this series by maybe a third by not repeating the same material across episodes. still, for people interested in the subject, it is a fascinating series.