23. The murder of James Bulger

“According to Wiki: ‘James Patrick Bulger (16 March 1990 – 12 February 1993) was a boy from Kirkby, England, who was murdered on 12 February 1993, at the age of two. He was abducted, tortured and murdered by two ten-year-old boys, Robert Thompson (born 23 August 1982) and Jon Venables (born 13 August 1982).'” — LilTrins

24. David Parker Ray

“David Parker Ray was a serial killer, kidnapper and rapist. He converted a mobile home into a torture chamber. Messed up, but the worst is an transcript of audio tapes he allegedly played to his victims when he had just kidnapped them, where he described how he would torture and rape them in the coming months.” — davaca

25. Dennis Rader

“The serial killer BTK actually worked for a security company for some time installing alarms to clients that wanted to keep the killer out of their homes.” — druthers25