Nicknamed 'The Dating Game Killer' after his 1978 appearance on the TV show of the same name while in the middle of a killing spree, Rodney Alcala died on July 24, 2021. Although convicted of seven murders, investigators speculate there are more victims.

True-crime author Michael Arntfield talks about homicide detective Pat Postiglione, who headed up Nashville's cold-case Murder Squad and solved dozens of unsolved murders, and how the country-music mecca became a murder hub.

Doctors who murder are a rare breed, but perhaps because their entire mission is to do no harm, they are among the most chilling kind of killers. Texas surgeon Dr. Christopher Duntsch is one such physician who violated his oath so profoundly by intentionally botching surgeries that he became known as 'Dr. Death.'

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.

Read an excerpt from Michael Arntfield's true-crime book, 'Monster City,' about serial killer Tom Steeples, a computer store owner who found two of his victims, a newly married couple, at a dive bar's amateur showcase.

Although cannibals have always existed throughout human history as a cure for overpopulation, a means of survival during a famine, or even a way to contend with grief, what's more rare are murderers who kill for sport and then devour their victims. We talk to Dr. Eric Hickey, a forensic psychologist, on why some killers eat their prey.

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.

Read an excerpt from FBI Special Agent Jeffrey L. Rinek's book, 'In the Name of the Children,' about his interrogation of Yosemite Killer Cary Stayner over pizza.

Some studies claim male sexual-homicide offenders over age 50 are rare—murders committed by them account for only 0.5 percent of sexual homicides in the U.S.—which may be due to steep declines in their testosterone levels. But could a decline in testosterone really put a halt to a killer's murderous spree?

Gary Leon Ridgway, who raped and murdered more than 49 women, was obsessed with deviant sex and visiting prostitutes. This, combined with his aggression and violence, were significant driving forces behind his murderous actions, says Mary Ellen O'Toole, a retired FBI senior profiler who interviewed Ridgway.