We speak with experts about the various reasons why notorious murderers become targets themselves while behind bars.

A&E True Crime spoke to Zeman about the findings that made him, along with investigative journalist Maury Terry, question the official account that serial killer David Berkowitz acted on his own.

Read about the death of the businessman and children's entertainer, who liked to dress as 'Pogo the Clown' and was convicted in March 1980 of murdering 33 boys and young men, making him the worst serial killer in American history at the time.

Rather than deny or confess, some murderers blame others for their horrendous crimes.

In the late 1960s, Liza Rodman spent summers hanging out with Tony Costa, the handyman at the Royal Coachman hotel, where her mother worked. One of the many people Liza's mom enlisted to watch the 8-year-old and her sister, Tony was also a serial killer.

Investigative historian Peter Vronsky explains how Edmund Kemper, Ted Bundy, Jeffrey Dahmer and others reached celebrity status during the 'Golden Age' of American serial killing.

Jeffrey Dahmer was just 18 when he committed his first murder, much younger than the average age of serial killers, which researchers have determined is around 29 years old. Why did he wait nearly a decade before killing his next victim?

Over nearly two decades, Dennis Rader murdered at least 10 people in the Wichita, Kansas area under the pseudonym BTK ('Bind, Torture, Kill'). But despite his repeated taunts to the police and media, investigators were unable to hone in on a suspect.

Gary Heidnick's crimes helped inspire Buffalo Bill's character in 'Silence of the Lambs.' We spoke with the killer and self-described pastor's defense lawyer, Charles Peruto, Jr., about what it was like representing one of Philadelphia's most infamous criminals.

In December 2020, a team of civilian codebreaker broke one of the unknown killer's messages after 51 years. Are we now closer to finally finding out who he is?