Russian serial killer commonly referred to as "The Chessboard Killer" who is thought to have murdered at least 49 people in Bitsa Park in Moscow. He was convicted in October 2007 and sentenced to life in prison.
He suffered a severe head injury as a child which resulted in him being sent to a school for children with learning disabilities.
He was captured after authorities discovered a metro ticket on one victim's body, leading them to the metro system's surveillance footage, which depicted the victim walking with Pichushkin.
He lived with his paternal grandfather, whose death sent him into a spiral of alcoholism.
His crimes are often compared to that of fellow Russian serial killer Andrei Chikatilo.