20 Most Terrifying and Disturbing Serial Killers

20 Most Terrifying and Disturbing Serial Killers
VOICE OVER: Peter DeGiglio WRITTEN BY: Jordy McKen
These are the worst serial killers of all time. For this list, we'll be looking at the creepiest multiple-fatality felons that kept us up late at night due to their terrible actions and unsettling behavior. Our countdown includes Dennis Rader, Albert Fish, Jeffrey Dahmer, H.H. Holmes, and more.

20 Most Terrifying and Disturbing Serial Killers

Welcome to WatchMojo, and today we’re examining the 20 Most Terrifying and Disturbing Serial Killers.

For this list, we’ll be looking at the creepiest multiple-fatality felons that kept us up late at night due to their terrible actions and unsettling behavior.

Which of these appalls you the most? Let us know below.

Dennis Rader

Having named himself BTK after his modus operandi, for twenty years Rader was a massive thorn in the side of the police in Kansas. Like the infamous Jack the Ripper, he sent mocking letters to the cops and media. But in person, Rader seemed nice. He had a loving family and was president of his local church congregation. His first victim was the Otero family in 1974, and his tenth and last victim was Dolores Davis in 1991. Then, he dropped off the map. But in 2004, he began taunting them once again. However, he got sloppy with a floppy disk, and it was traced to his church. In 2005, Rader pleaded guilty and got ten consecutive life sentences.

Robert Hansen

As a teenager, Robert Hansen would take part in hunting to escape his rough home life. But, as he got older, his victims went from animals to human beings. He would abduct women, often sex workers, and assault them before driving or flying them out to the wilderness. Here was where he would hunt them down like prey, toying with their lives. Nicknamed the “Butcher Baker” by the media, Hansen was confirmed to have assaulted and killed at least seventeen women. In 1983, a teenage sex worker named Cindy Paulson was set to be on that list. However, she managed to escape when he was stocking his plane and alerted the authorities who would arrest him. He received a sentence of 461 years and died in prison after serving thirty-one years.

Israel Keyes

What’s most terrifying for the police and the public is a killer with no M.O. But, to make things worse, how about one who was also trained by the U.S Army? This was the case of Israel Keyes. Across the country, Keyes had set up “kill kits,” which gave him access to equipment wherever he decided to attack someone. After he killed eighteen-year-old Samantha Koenig, the FBI was able to track his bank account use and make an arrest following the demand for a ransom. Once he was in custody, however, it was discovered that Keyes was responsible for the murder of multiple victims. Before he faced trial in 2012, Keyes took his own life, and took with him information that might have been used to solve other cases.

Marcel Petiot

With France under German occupation in the 1940s, Marcel Petiot, a doctor, preyed on those attempting to escape persecution. Later claiming he was working for the resistance, even though there was no evidence, Petiot set up a fake escape route under the name “Dr. Eugène.” He gave those running a fake vaccine that contained cyanide before stealing their valuables and disposing of their bodies. Twenty-three remains were discovered, but Petiot’s lifetime victim count is suspected to be as high as sixty, if not higher. In 1946, Petiot was executed by guillotine, which was still the country’s method of capital punishment at the time.

Karl Denke

Born in modern-day Poland in 1860, Karl Denke appeared to be a beloved member of his community. After all, they had nicknamed him “Papa” as he let homeless people live in his house for free and volunteered at his local church for a time. But away from prying eyes, he held a very dark secret. In 1924, a badly injured Vincenz Olivier alerted townsfolk that he was attacked by Denke. While the authorities didn’t believe him, they later arrested their stand-up citizen as they investigated. Shortly after, Denke took his own life. The police then found human remains of at least thirty people in his house, some of which were made into items. There’s also speculation Denke sold the remains to unsuspecting locals.

Joseph James DeAngelo

Police officers are meant to be honorable and find justice for victims, not cause a wake of destruction like Joseph James DeAngelo. In 1976, he began his spree of assaults and burglaries in Sacramento, California. In the space of three years, he had committed fifty attacks. By 1978, DeAngelo progressed by slaying Brian and Katie Maggiore. He morphed into the “Original Night Stalker” and later the “Golden State Killer” before the crimes stopped in 1986. Then, in 2018, the police used genetic genealogy from the DNA found at DeAngelo’s crimes to trace it back to him. In 2020, amongst several charges, he pled guilty to thirteen murders as part of a deal to avoid capital punishment and got a life sentence.

Dean Corll

After leaving the army in 1965, Dean Corll returned to Houston, Texas to work in the family candy business. He was known to hand out free treats to children, earning him the nickname the “Candy Man.” Shortly after, he began a relationship with the underage David Owen Brooks. When Corll began his killing spree in 1970, Brooks helped him select victims. Corll then got Elmer Wayne Henley involved, too. In 1973, after slaying twenty-eight people, Corll decided to take out Henley, along with two other victims. The teenager managed to convince Corll he was on his side. But when the opportunity arose, Henley fatally shot his former mentor. Both Brooks and Henley received multiple life sentences.

David Parker Ray

Sometimes, killers go that extra, terrifying mile with their modus operandi. David Parker Ray modified a trailer that would be labeled his “toy box.” The trailer was soundproofed and filled with instruments for his violence. He would abduct women, abuse them for months in the trailer, and presumably, eventually end their lives, sometimes with accomplices, one of them being his girlfriend, Cynthia Hendy. In 1999, a woman managed to escape the “toy box” after three days and get help from a neighbor. The police immediately arrested Ray and Hendy. On a plea deal, Ray was sentenced to 224 years in jail, while Hendy, who testified against her former partner, got thirty-six years. It’s unknown how many women Ray killed, but some estimates are upwards of sixty.

Edmund Kemper

At six-foot-nine, Edmund Kemper was an intimidating figure. But with his gentle demeanor, he seemed harmless. However, as a teenager in 1964, he fatally shot his grandparents. Five years later, he was released from a psychiatric hospital and went to live with his abusive mother, Clarnell Strandberg. By 1972, Kemper began driving around Santa Cruz, California, picking up young women who were hitchhiking. He would act impatiently, which enticed them inside the vehicle since they believed he was too busy to be an attacker. But he was. This MO earned him the nickname the “Co-Ed Killer.” In 1973, he brutally killed his mother and her friend before handing himself to the police. With ten victims altogether, Kemper received a life sentence.

Andrei Chikatilo

He having grown up in difficult circumstances in rural Ukraine under USSR rule, something broke in Andrei Chikatilo. But to the outside world, all seemed okay. He had a wife, two kids, and began working as a schoolteacher in 1971. But not long after getting the job, Chikatilo began assaulting pupils. By 1978, he moved on to killing, with his wife providing him an alibi. Using jobs that required traveling as a cover, by 1990, Chikatilo claimed to have slain fifty-six people, mostly in the Rostov Oblast, earning him the moniker of the “Butcher of Rostov.” After being arrested and later confessing to his tirade of crimes, Chikatilo was held in a cage in court. He was found guilty and executed in 1994.

Ted Bundy

In the 1970s, many women came to the aid of a man, often appearing injured, who needed help in one form or another. With his good looks and charisma, this mystery guy seemed genuine. Instead, he was one of the most infamous killers in history as he forced his victims into his car. Ted Bundy escaped capture multiple times, continuing his grim spree as he did. But by 1980, he faced court for the final time. Bundy had confessed to slaying thirty women and teenagers across multiple states in the US. However, there’s speculation that the true figure could be over 100. For the third and final time in his life, Bundy was sentenced to capital punishment, which took place in 1989.

Ed Gein

Serving as inspiration for several horror movie villains, such as Buffalo Bill in “The Silence of the Lambs” and Leatherface in “The Texas Chain Saw Massacre,” Ed Gein was a disturbing killer. He was raised by an abusive mother that taught him that women were evil. In 1957, one Bernice Worden vanished in Wisconsin. Following a lead, the police arrived at Gein’s isolated house and discovered a terrible scene. On top of Worden’s body, they found a catalog of items made from human remains. Altogether, there were pieces made from around forty people. Gein claimed he grave-robbed most of the remains. In 1968, he was deemed fit to stand trial and was found guilty of Worden’s slaying. Gein spent his remaining years in psychiatric hospitals.

John Wayne Gacy

One pretty common phobia is clowns. And the case of John Wayne Gacy certainly didn’t help ease any of those fears. Gacy regularly performed in a clown persona at parties and events; but, behind the scenes, he was a rampant killer of boys and men. In 1978, after suspecting the police were onto him, a paranoid Gacy would confess his crimes to his lawyers. The police had what they needed to search his house, where they would find several remains in his crawl space. He was charged with the assassination of thirty-three young men and would spend fourteen years on death row before being executed by lethal injection.

Fred & Rosemary West

Occasionally, serial killers come in pairs. While Fred had murdered in the past before meeting Rosemary Letts, Rose’s first victim was, purportedly, Fred’s stepdaughter. The two then went on a rampage, assaulting and killing nine other people together, including West’s first wife Catherine Costello and their daughter Heather West. Many of the bodies were buried on their properties. After investigating assault charges against the couple, the police found evidence of the violence. Although officially charged with twelve killings altogether, that number is estimated to be higher. In 1995, before his trial, West took his own life and Letts was sentenced to life in prison.

Jeffrey Dahmer

From his late teens, Jeffrey Dahmer began a horrific killing spree. His victims were all men or boys, and many of his later crimes involved unspeakable acts to the bodies. In 1991, Dahmer enticed Tracy Edwards back to his apartment with the promise of beer and payment for photographs. However, Edwards realized something was wrong and managed to escape. After he flagged down police officers, Dahmer’s apartment was investigated and grim evidence was found, leading to Dahmer’s arrest. He was convicted of fifteen murders and sentenced to life imprisonment. However, in 1994, he was fatally attacked by fellow inmate Christopher Scarver.

Albert Fish

Nearly 100 years ago, New York had a killer on the loose nicknamed many things including “The Gray Man” and even “The Boogey Man.” (Honestly, it’s not too far off.) Albert Fish was a disturbed individual who targeted children. While we can’t exactly list off his crimes toward them, just know they’re terrible. To make things even more disturbing, the unhinged Fish sent the mother of one of his victims a letter describing what he did. Ten years after Fish began his acts, he was captured in 1934 after witnesses claimed to have seen him with the missing children. Fish would admit to the murders, but would also claim he had over 100 victims. At his trial the following year, he was sentenced to execution, which was carried out in 1936.

H. H. Holmes

Thought of as one of the US’s first serial killers, Herman Webster Mudgett, better known as H. H. Holmes, dabbled in fraud in his early years to earn cash. Then, he constructed what would be nicknamed the “Murder Castle” in Chicago, Illinois. It contained secret passageways and trap doors that allowed Holmes to slay privately and dispose of the evidence in the basement’s furnace. He would usually entice women into the building and later opened it up like a hotel. In 1894, Holmes was arrested for a different crime before his killing was discovered. He confessed to twenty-seven victims, but loftier speculations have the number over 200. In 1896, Holmes was executed for his grim crimes.

Samuel Little

In 2019, the FBI confirmed that they’d identified Samuel Little as the most prolific serial killer in US history. After being convicted for slaying three people in 2014, the unsettling extent of his crimes began to leak out over the next few years. By 2018, Little had confessed to killing ninety-three women across the country. Little provided the FBI with details on many of the cases from 1970 to 2005 and even drew the victims from memory to prove he was telling the truth. Before he passed away in 2020, more than sixty of Little’s confessions across at least fourteen states had been confirmed by the authorities.

Harold Shipman

Doctors are meant to be people we all trust. This makes the case of Harold Shipman especially chilling. He was a general practitioner in England who took people under his care only to end their lives. In 1998, one of his patients suddenly passed away, and a will – one that the family knew nothing about – gifted a lot of cash to Shipman. Police investigated the doctor and found evidence of forgery. Upon further examination, they found that many of his patients seemed to pass from overdoses of diamorphine. In 1999, Shipman was charged with the murder of fifteen patients, many of whom were older women. He was sentenced to life in prison and, in the aftermath, there were thought to be as many as 250 victims.

Pedro López

What’s worse than a serial killer? Well, how about a known one authorities can’t currently locate? Born in Columbia, Pedro López was a serial murderer across South America and was nicknamed “The Monster of the Andes.” In 1980, after attempting to abduct someone, López was arrested in Ecuador. He was soon charged with 110 homicides; however, López reportedly confessed that his victims could total more than 300. In 2006, the Guinness World Records actually named him the “most prolific serial killer” before it was taken down in bad taste. Unfortunately, López was released for “good behavior” in 1998 and was declared sane. But, as of 2002, after being linked to another murder, his whereabouts are unknown.