'Beware the Slenderman' explores the disturbing case that shocked the internet
HBO's gripping doc is a must-see expedition into chilling crimes.
HBO's 'Beware the Slender Man' explores the internet's 'dark basement'
Truth is stranger than fiction.
Teen in 'Slender Man' case pleads not guilty due to mental illness
Morgan Geyser and Anissa Weier are accused of stabbing a 12-year-old girl while attempting to summon 'Slender Man'