From putting himself on the stand to proposing to his girlfriend in court, we look at some of the most outlandish moments from the serial killer's murder trials.

For Jeffrey Dahmer, it was watching certain movies. Dennis Rader, known as the BTK Killer, set the mood by pretending he was a spy. Ted Bundy liked drinking alcohol before some of his slayings. Not every serial killer has a signature routine, but some of them do engage in some sort of ritual or preparation before a killing.

Peter Vronsky, author and investigative historian, speaks with us about ancient killers, the influence of technology on crime and how, in 100 years, the Long Island Serial Killer could be the new Jack the Ripper.

Tricia Griffith, who runs the web forum Websleuths, talks to A&E True Crime about her close encounter with Ted Bundy, how the online community dug into the Casey Anthony case and why she believes police should let amateur detectives help investigations.

A&E True Crime talks to retired FBI profiler Dr. Mary Ellen O'Toole about serial killers, like Ted Bundy and the Toolbox Killers, who had well-defined victim preferences.

Dr. Mike Aamodt, forensic psychology professor at Radford University, on why female serial killers have declined over the years, why there was a big jump in serial killings in the U.S. between the 1960s and 1980s and his most surprising finding in his research of serial killers.

From Green River Killer, Gary Leon Ridgway to Ted Bundy to Harold Shipman and more, experts on serial killers tell A&E True Crime who was the 'worst' serial killer and why.

Psychologist Al Carlisle, who was part of a diagnostic team at Utah State Prison who evaluated Ted Bundy, talks about the serial killer's lonely childhood, participation in illegal activities at a young age and strong desire to control women, which Carlisle believes led to his psychopathic tendencies as an adult.

Why do so many killers—Jeffrey Dahmer, Ted Bundy and David Berkowitz to name a few—abuse animals before targeting people? An expert provides insights on how the two behaviors are linked.

Ted Bundy received hundreds of love letters while behind bars. Richard Ramirez married one of his 'fans.' Criminologist Dr. Melissa Hamilton talks to A&E True Crime about the psychology behind why some women love serial killers.