World's Most Evil Killers Episode Rating Graph

Billy Mansfield Jr murdered at least five victims, but investigators suspect the extent of his serial killing is still to be revealed.

A Texas serial killer, Anthony Allen Shore was matched to four murders after his arrest for a different crime.

The notorious story of a man convicted of the murder of two young girls, as well as another killing at a military base.

A killer who found some of his victims through ads, the case of Paul Runge become prominent in the debate over the death penalty in Illinois.

A man who terrorized Phoenix in an extensive year-long crime spree, committing nine murders with no apparent motive.

The Alaska serial killer Robert Hansen who murdered at least seventeen women during a spree that lasted for more than a decade.

The Molalla Forest Killer: The story of the brutal killer who targeted women on the street and dumped their bodies in the forest.

A profile of the Rhode Island family man and Sunday school teacher, who also turned out to be a cold-blooded triple murderer.

A profile of the murderer known to some as the Riverside Prostitute Killer, who sits on death row after being convicted for the slaying of 12 women.

A chilling profile of the serial killer Todd Christopher Kohlhepp, who claimed the lives of at least seven innocent people between 2003 and 2016.

A look at the life - and horrifying crimes - of Ted Bundy, a notorious serial killer who murdered at least 30 young women and girls between 1974 and 1978.

Known as The Railroad Killer to some, the serial killer is thought to have taken the lives of more than 23 victims before his execution in 2006.

A profile of the serial killer who found himself at the center of New York's biggest manhunt after a vicious shooting spree that left six dead.

Also known as the Yosemite Park Killer, Cary Stayner murdered four women in 1999 before his capture. Were his actions the result of a tragic childhood?

Sunset Strip Killers: The story of two killers who targeted young girls and sex workers for their own twisted pleasure. Descriptions of sexual violence and child abuse.

An investigation into the murderous mother-and-son duo, who killed their elderly landlady in a greed-fuelled ploy.

A profile of the serial killer who took the lives of six victims in one month, known to some as The Vampire Killer due to his penchant for cannibalism.

A look at the life of the Polish serial killer, nicknamed the Vampire of Krakow for his wildly varying choice of victims, from young children to the elderly.

Over a 25-year career of murder, Richard Biegenwald killed at least six people as he sought out ever more violent and inventive ways of dealing death.

In 1973, Dawn Magyar's body was found two months after she had vanished. Twenty-eight years on, advances in forensics helped solve the case.

The story of the "Death House Landlady", who took in elderly and disabled tenants, only to murder them for their social security paychecks

Exhibiting cruelty, callousness, and viciousness beyond any human understanding, Richard Ramirez terrorized Los Angeles with his spate of home invasions.

A look at the cold-hearted criminal who was convicted of murdering her daughter and attempting to kill her two other children in 1983

The chilling story of the serial killer who worked as a nurse in Texas, where she killed many children and infants by injecting them with drugs.

An in-depth look at the life and crimes of William Devin Howell who was found guilty of the murders of seven different women

A profile of Ed Gein, the killer and body-snatcher who came to be known as the `Butcher of Plainfield', and whose story is thought to have inspired Alfred Hitchcock's Psycho.

The story of the serial killer Sean Vincent Gillis, who brutally snatched away the lives of eight innocent women during a decade-long killing spree in Louisiana.

A profile of Derrick Todd Lee, who murdered seven women in the Baton Rouge area of Louisiana, and was sentenced to death for his chilling crimes.

For nearly a decade, the Bayou Strangler deceived, bound, assaulted and murdered men, as he drifted across South Louisiana.

An examination of the Polish serial killer, who came to be known as "The Scorpion" after murdering nine women and attacking eleven others.

Examining the crimes of Glen McCurley, who in 1974 abducted 17-year-old Carla Walker from a bowling alley car park and killed her before leaving her body in a ditch

An insight into the crimes of Jeffrey Dahmer, the American serial killer dubbed the `Milwaukee Cannibal' after he raped, murdered and dismembered 17 people between 1978 and 1991

The story of Judy Buenoano, the first woman in Florida to die in the electric chair. She was a killer so evil that her own son became one of her victims.

A profile of The Truck Stop Killer, who targeted hitchhikers and truck stop sex workers in a horrific string of crimes spanning 15 years.

The Shoe Fetish Killer: The crimes of Jerry Brudos, whose disturbing shoe fetish played a part in the gruesome murders he carried out on four young women.

The Happy Face Killer: A profile of the serial killer, whose chilling confession letters to the media and prosecutors were signed off with smiley faces.

John Allen and Lee Malvo: The story of the Beltway sniper attacks. John Allen and his teenage accomplice carried out the brutal series of shootings that killed 10.

The story of one of the most prolific serial killers in Canadian history, dubbed `The Pig Farmer Killer' by the media.

An insight into the crimes of Thierry Paulin, who attacked, robbed and murdered at least 18 elderly women in France during the 1980s, to fund his extravagant lifestyle.

The story of the Austrian serial killer Jack Unterweger, who was heralded as an example of successful rehabilitation, only for him to kill again.

The case of 'The Pink Giant', Wolfgang Schmidt, a transgender German serial killer who brutally murdered five women and an infant.

The Grim Sleeper: The story of the brutal Los Angeles serial killer. Nine innocent women and a teenage girl lost their lives at his hands

A profile of the triple-murderer who killed his ex-girlfriend, her nine-year-old daughter and another man in a brutal attack.

Serial killer Gary Ray Bowles, who took the lives of six men in 1994, and became known as the I-95 Killer, as most of his victims lived close to the Interstate 95 highway.

The story of Velma Barfield, the first woman to be executed by lethal injection after taking six lives.

Responsible for five murders, Joshua Wade avoided justice for years and later confessed to killings that started from when he was just 14.

Paul Michael Stephani has become etched in the minds of all who knew him as the notorious weepy voiced Killer, whose rage fueled and vicious attacks took the lives of three unsuspecting women.

In 1999 and 2000, women began disappearing from Detroit's thriving areas of prostitution. No one suspected that John Eric Armstrong, a seemingly normal father was actually a killer.