On November 15, 1990, a 2-year-old boy, Billy Blankenship, was reported to have fallen down the stairs in his babysitter's care in Concordia, Missouri. The sitter, Tawny Sue Gunter, claimed she had put the boy in her basement as she prepared lunch upstairs. The boy suffered a skull fracture and later died. But that wasn't the end of the story.

The United States may have churned out the highest number of serial killers in the world over the years, but it certainly doesn't hold exclusive rights on brutal murders. Learn about some international serial killers and how their respective countries handled their crimes.

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.

A&E True Crime looks back on Columbian drug lord Pablo Escobar's rise to power and prosperity, and investigates who fired the bullet that took his life.

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.

After the 2005 disappearance of Teresa Halbach, 16-year-old Brendan Dassey confessed to police that he and his uncle, Steven Avery, raped and murdered her. But Dassey later recanted his confession, suggesting that he'd been coerced into telling the police what they wanted to hear. The jury didn't buy it and sentenced him to life in prison.

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.'

Researchers have found the vast majority of people who kill their families (familicide), are men with a history of violence toward their spouse and children. But what tips the scale from abuse to murder? And which men are most likely to kill? We spoke to a professor of forensic psychology for answers.

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.

On September 29, 1982, and in the few days that followed, seven people in the Chicago area died in Tylenol-related poisonings. The capsules were all laced with cyanide. The killer or killers have never been found.