10 Serial Killers With Unimaginable Kill Counts

10 Serial Killers with Unimaginable Kill Counts

Welcome to WatchMojo, and today, we’ll be examining both the staggering number of confirmed murders attributed to serial killers and the even higher totals they allegedly claimed or that investigators and other experts have theorized.

Thug Behram

Before the likes of Jack the Ripper or Ted Bundy became household names, another killer's legend spread across colonial India. Thug Behram allegedly led bands of Thuggee robbers who befriended unsuspecting travelers before strangling them with ceremonial cloths and burying the bodies. British authorities eventually dismantled the organization through informants and widespread arrests during the 1830s. Behram confessed to personally strangling 125 victims while participating in many more killings. Guinness World Records once credited him with involvement in over 931 murders, though modern historians widely dispute that astonishing figure. They call that number improbable, even a brag, since it would require a killing every five days across four decades. As for Behram’s end, it’s widely believed he was executed by hanging in 1840.

Andrei Chikatilo

The Soviet Union refused to believe it had a serial killer, allowing one of history's deadliest murderers to keep hunting for years. Between 1978 and 1990, Andrei Chikatilo preyed on women and minors, luring them to secluded areas in deadly attacks fueled by violent sexual impulses. Despite mounting evidence, a flawed blood-type test in 1984 ruled him out as a suspect, while false confessions repeatedly derailed the investigation. His luck finally ran out in November 1990 when a patrolman noticed his suspicious behavior near a railway station. Police placed him under surveillance, gathered enough evidence to connect him to the crimes, and secured a confession to at least 56 murders. Chikatilo was convicted of 52 killings, sentenced to death, and executed by gunshot in 1994.

Charles Cullen

For 16 years, Charles Cullen quietly turned hospital wards into hunting grounds while no one realized a trusted nurse was secretly killing patients. Nicknamed the "Angel of Death," he worked at around nine hospitals across New Jersey and Pennsylvania, administering fatal overdoses of insulin, digoxin, and other heart medications. Cullen insisted he was ending suffering, but investigators found many victims weren't terminally ill, suggesting his real motive was more twisted. His spree ended in 2003 after fellow nurse Amy Loughren helped detectives expose him. Cullen pleaded guilty to 29 murders, though experts believe he may have killed as many as 400. Hospitals repeatedly let him resign without reporting suspicions, leaving many deaths uninvestigated, and Cullen admitted he could not remember all his victims.

Albert Fish

Even among history's most depraved killers, Albert Fish stood apart for pure cruelty. Through the 1920s, he kidnapped, tortured, murdered, and sometimes cannibalized his victims, then vanished back into ordinary life as a quiet house painter. Nothing caught up with him until 1934, when he mailed Grace Budd's mother a letter describing her daughter's 1928 murder in stomach-turning detail. Detectives traced the stationery to a boarding house and arrested him. Though convicted only for Grace Budd's death, Fish confessed to killing at least two more minors. He separately claimed he'd assaulted around 100 minors nationwide, mostly Black or disabled minors he believed police wouldn't bother investigating. He died in the electric chair at Sing Sing Prison in 1936.

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Mariam Soulakiotis

Behind the image of a devout religious leader lurked a woman many came to call "Mother Rasputin." Mariam Soulakiotis ran a Greek convent promising care for vulnerable women, children, and tuberculosis patients, while allegedly exploiting them all for money and property. Scrutiny began when a woman reported her mother's will had suspiciously been changed to benefit the convent, then intensified after the FBI traced a missing Ohio teenager there. In December 1950, officers raided the convent, finding malnourished residents alongside thirty-six children kept locked away. Prosecutors ultimately tied Soulakiotis to at least 177 deaths. Authorities at one point believed the true number could exceed 500, based on property records showing many people had willed their assets to the monastery before dying there.

Kermit Gosnell

What investigators expected to be a routine drug raid uncovered one of America's most disturbing medical crime scenes. Inside Dr. Kermit Gosnell's Philadelphia clinic, authorities found filthy conditions and illegally stored fetal remains. Also found was evidence that newborns delivered alive during late-term abortions had their spinal cords severed. The investigation also revealed dangerous practices that contributed to the death of one patient. Testimony suggested Gosnell and his staff had carried out hundreds of illegal procedures over many years. In 2013, he was convicted of three counts of first-degree murder involving infants born alive, involuntary manslaughter for a patient's death, and numerous other offenses. He received multiple life sentences without parole and died in prison in 2026.

Mikhail Popkov

He spent years investigating murders while secretly committing them himself. Around the Siberian city of Angarsk, former police officer Mikhail Popkov hunted vulnerable women. After offering them rides, he brutally killed them with weapons he pulled from evidence lockers. For two decades, he evaded suspicion, even inspecting some of his own crime scenes. Then in 2012, tire tracks from his patrol vehicle led investigators to run DNA on 3,500 officers, matching him instantly. Courts convicted him of over 20 murders in 2015 and over 50 more in 2018. Further trials in 2021 and 2023 pushed his confirmed total past 80, with confessions suggesting he may have killed closer to 90. He remains Russia's most prolific known serial killer, still serving multiple consecutive life sentences.

Luis Garavito

Minors across Colombia vanished with terrifying regularity before investigators realized one predator was behind many disappearances. Often posing as a monk or street vendor, Luis Garavito lured minors with gifts, money, and promises of work, proceeding to do the unspeakable. In April 1999, a boy escaped an assault and alerted authorities, leading to Garavito's arrest under a false name. A prison-wide eye exam matched his prescription to glasses found at a crime scene, and DNA sealed the case. Garavito confessed to more than 190 murders, but investigators believe the toll may reach 400, since many victims were poor or unhoused minors never reported missing. Despite sentences totaling over 1,800 years, Colombian law capped it at 22. Garavito died in prison in 2023.

Samuel Little

For decades, he slipped through the cracks by targeting people society overlooked. Between 1970 and 2005, Samuel Little preyed on vulnerable women, many struggling with substance use disorder or living on the streets, across nineteen states. Coroners frequently ruled his victims' deaths as overdoses or accidents, letting Little evade capture. Police arrested him in 2012 on an unrelated drug charge, then DNA tied him to three unsolved murders. Little later confessed to 93 killings total, describing victims' faces and locations of murders with striking accuracy that sometimes matched sealed autopsy records and unpublished crime-scene details. Investigators have verified more than 60 through DNA and corroboration, and the FBI calls him America's most prolific serial killer. He died in custody in 2020.

Harold Shipman

Patients trusted him completely with their own lives, never once suspecting their family doctor was quietly becoming Britain's most prolific serial killer. Over more than two decades, Harold Shipman preyed mostly on elderly women, administering lethal doses of diamorphine before falsifying medical records to make deaths appear entirely natural. Shipman's downfall began after he forged one victim's will, raising suspicions among her family. Police then uncovered exhumed bodies with unusually high morphine levels. In 2000, Shipman was convicted of murdering 15 patients, but a later inquiry concluded he had likely killed around 250 of them. The inquiry found that 459 people had died under his care between 1971 and 1998. No one knows which of these were real murder victims or died naturally.

Which of these kill counts stunned you the most? Let us know in the comment section.