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Dennis Rader -

Dennis Rader was known as the "BTK Killer," a name he gave himself in the taunting letters he sent to police and the media during his two-decade killing spree. BTK stands for "bind, torture, kill"—his modus operandi.

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Dennis Rader -

Rader killed 10 people between 1971 and 1994, but was only caught in 2005. This was partly thanks to the fact that he held onto mementos from his crimes, including the victim's driver's licenses and photos of their bodies.

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Ted Bundy -

Ted Bundy was one of the most prolific serial killers in American history. The charm and intelligence he employed to lure his victims made his crimes even more disturbing. It's believed that he brutally murdered at least 36 women.

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Ted Bundy -

Bundy told police that he decapitated 14 of his victims and kept their heads to play with, even doing their hair and putting makeup on them. "If you’ve got time, they can be whatever you want them to be," he reportedly told detectives.

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Jeffrey Dahmer - Jeffrey Dahmer, also known as the "Milwaukee Cannibal," murdered and dismembered 17 men and boys between 1978 and 1991. He first started collecting body parts as trophies when he preserved the head and private parts of one of his victims in acetone.

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Jeffrey Dahmer -

His habit grew and he eventually had a freezer full of dismembered body parts. When he was finally arrested, the first responder at the scene opened the fridge to find a freshly severed man's head sitting on the bottom shelf.

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Ed Gein -

Ed Gein was a heinous serial killer active in the US in the 1950s. He was initially caught for stealing dead bodies from graves, but later confessed to murdering two women. Although the number of deaths associated with Gein is low, the horror of his actions inspired some of the most chilling characters in film history.

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Ed Gein -

Gein was known for collecting the skin of his victims to fashion into various items, including masks, corsets, and lampshades. His house of horrors (pictured) astounded the police in small-town Wisconsin. Gein was the inspiration for characters like Leatherface in ‘The Texas Chainsaw Massacre’ franchise, Norman Bates in ‘Psycho’ (1960), and Buffalo Bill in ‘Silence of the Lambs’ (1990).

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John Wayne Gacy -

John Wayne Gacy, the terrifying killer clown, murdered and assaulted at least 33 young men and boys during his reign of terror. When police connected him to a schoolboy's disappearance and searched his home, they found mementos he had taken from multiple other victims.

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John Wayne Gacy -

One of the personal items they found was a class ring that belonged to another high school boy who disappeared shortly after graduating. This discovery would start to connect Gacy to a number of other disappearances, and eventually the awful scale of his crimes was revealed.

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Joel Rifkin -

Joel Rifkin was a serial killer active in Long Island in the early 1990s. He was convicted of killing nine women, but it's believed that he actually took a total of 17 lives. He was arrested in 1993 when police pulled him over for driving without a license plate and found a body under a tarp in his car.

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Joel Rifkin -

Rifkin confessed to his crimes and led police to his house, where they found a treasure trove of souvenirs he had taken from his victims. The items he kept included underwear, driver's licenses, jewelry, and one library card.

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Ed Kemper - Ed Kemper, also known as the "Co-ed Killer," murdered six female college students in the early 1970s. He had already served a juvenile detention sentence for murdering his paternal grandparents when he was 15 years old.

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Ed Kemper -

Kemper concluded his killing spree by murdering and decapitating his mother, who psychologists believe was always the focus of his murderous desires. He kept her head and used it as a dartboard before eventually turning himself in to the police.

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Anatoly Onoprienko - Anatoly Onoprienko was a prolific Ukrainian murderer who gained the nickname "The Terminator." He killed 52 people, with most of the crimes occurring within the same year.

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Anatoly Onoprienko -

When he was arrested in 1996, police found over 100 items belonging to the victims in Onoprienko's possession. It appeared that he had taken the underwear of all of his female victims.

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Dennis Nilsen - Dennis Nilsen was Britain's answer to Jeffrey Dahmer. He lured vulnerable men to his apartment with the promise of alcohol and company, before eventually strangling them to death. He would then wash the bodies, dress them again, and violate them.

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Dennis Nilsen -

Nilsen held onto the body parts and organs of his victims, which eventually led to his arrest. His neighbor's sink became blocked with what turned out to be human flesh he had tried to flush and became stuck in the pipes. Police found bags of human remains when they searched his apartment.

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Alex Mengel -

Alex Mengel was first apprehended as a suspect in a police killing in 1985. He shot a police officer at a random traffic stop and was later arrested after a car chase. Authorities found a number of strange items in his car, including what appeared to be a wig.

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Alex Mengel -

The car he was driving actually belonged to a woman who had recently disappeared, and the wig was actually her scalp and hair. Mengel had taken it after he killed her and seemed to be planning on impersonating her.

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Ivan Milat - Ivan Milat is known as the worst serial killer in Australian history. He was called the Backpack Killer because he would offer lifts to backpackers and hitchhikers. Milat drove his unsuspecting victims into the woods where he shot or stabbed them and buried their bodies.

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Ivan Milat -

When police raided his house, they found camping supplies he'd taken from his victims. They described it as an “Aladdin’s Cave” of sleeping bags, tents, and clothing.

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John Christie -

John Christie was another English serial killer responsible for at least eight deaths. He was nicknamed "The Rillington Place Strangler" as he always strangled his victims in his Rillington Place apartment.

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John Christie -

Rather than holding on to personal items or specific body parts, Christie stored entire corpses in his apartment. This led to his arrest after he sublet his home to renters who found three dead bodies hidden in a secret alcove in the kitchen.

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John George Haigh - John George Haigh, known as the "Acid Bath Killer," murdered at least six people in the 1940s, but may have killed as many as 10. The Englishman earned his name by dissolving the bodies of his murder victims in acid to get rid of the evidence.

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John George Haigh -

Haigh was careful not to keep many souvenirs lying around that could lead to his arrest. However, he broke his own rule after killing a wealthy couple named Archibald and Rose Henderson. He sold off most of their possessions but decided to keep their dog.

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David Parker Ray -

David Parker Ray, also known as the "Toy-Box Killer," may have been one of the most prolific serial killers in history, although no bodies were ever found. Ray would kidnap and abuse women for long periods before drugging them to erase their memories and releasing them. However, his accomplices say he killed many of the women, and police suspect his death toll may be as high as 60.

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David Parker Ray -

Ray died of a heart attack in 2002 without ever being convicted of murder. The FBI shared a lengthy list of photos on their website showing items they believed Ray had taken from his victims, in the hopes that someone would come forward to identify them. The items include underwear, jewelry, and even children's clothing.

Sources: (Oxygen) (Ranker) (Listverse)

See also: Infamous murderers who got married in prison

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