Serial Killers - The Chessboard Killer (NEW 2015) have killed at least 49 people !! FULL DOcumentary

Russia
https://en.wikipedia.org/wiki/Alexand...
http://www.biography.com/people/alexa...

Pichushkin is remembered to have been an initially sociable child. However, this changed following an incident in which Pichushkin fell backwards off a swing and was then struck in the forehead as it swung back. Experts have speculated that this event damaged the frontal cortex of Pichushkin's brain; such damage is known to produce poor impulse regulation and a tendency towards aggression. That this event happened when Pichushkin was still a child is also significant, as a child's forehead provides only 1/8 the protection for the brain of an adult's. Indeed, following this accident Pichushkin frequently became hostile and impulsive, and his mother decided to transfer him from a mainstream school to one for children with learning disabilities. Following this transfer, children from the mainstream school began to physically and verbally bully Pichushkin, referring to him as "that retard". This abuse served to intensify Pichushkin's rage and hostility. Upon his reaching early adolescence, Pichushkin's maternal grandfather recognized that Pichushkin was highly intelligent, and felt that his innate talents were being wasted, as he wasn't involved in any activities at home, and the school he was enrolled in focused more on overcoming disability than on promoting achievement.
https://youtu.be/HNUBHX_I0ZI