Mysterious Cold Cases That Have Baffled America for Decades

The American public is often captivated by crime. We watch programs like "Unsolved Mysteries" and "Law and Order," and there are even entire networks dedicated to all things crime, from Investigation Discovery (the ID channel) to the True Crime Network, and much more. Some cases are solved, although it may often take years. Others remain open. Many mysterious cold cases have baffled America for decades.

According to FBI statistics analyzed by theMurder Accountability Project, by 2023, 57.8 % of homicides were solved, a marked improvement from the previous year at 52.3 %. Yet, for that remaining percentage, there are still questions and no answers.

24/7 Tempo has compiled a list of mysterious cold cases that have baffled America for decades. We gathered information from the FBI, various media reports, and other sources, including regional publications. We concentrated on crimes that have remained unsolved for at least 15 years based on the latest available data.

This list is not exhaustive, and we used editorial discretion to identify the unsolved crimes that particularly captivated the public's interest and generated substantial media coverage. (Here is a list of the most famous major cases in FBI history.)

This post was updated on October 18, 2025 to clarify Borden's murder weapon, number of people that went missing in Vermont, what fire experts say about the Sodder children, origin of the nickname Black Dahlia, CBS's reporting on the Tylenol murders, details of the Ramsey murder, and date of Biggie Smalls murder.

Here are mysterious cold cases that have baffled America for decades:

• Crime: Murder
• Year: 1892

No other murder in U.S. history has been the subject of public fascination for as long as the fatal bludgeoning of the Bordens. It's almost certain that Lizzie Andrew Borden beat her affluent father and stepmother to death with a hatchet, possibly with the collusion of a housemaid.

A court ruled the evidence against her was circumstantial, however, and she was released to live out her days ostracized by her community. The murder captured the public's attention at the time and continues to show up in popular culture, most recently as the 2018 film "Lizzie."

• Crime: Murder
• Year: 1912

One of the most horrific unsolved multiple homicides in American history took place on the night of June 9 in Villisca, Iowa. In what became known as the "Villisca Axe Murders," a husband and wife and six children ages 5 to 12 were bludgeoned to death with an ax.

The still-unsolved crime influenced calls for professionalized investigation. Iowa's state investigation bureau later formed in the 1920s. Lyn George Jacklin Kelly, a traveling preacher with a history of mental illness, was detained and charged, but a deadlocked jury led to his acquittal.

• Crime: Abduction
• Year: 1920-1950

A wooded area around Glastenbury Mountain in southwestern Vermont has experienced an inordinate number of unexplained disappearances. Five people vanished between 1945 and 1950, including a 53-year-old woman, whose body was later discovered, and others whose bodies never were.

In 1992, author and folklorist Joe Citro dubbed the area of the disappearances "the Bennington Triangle," and noted that while some people believe the disappearances are a coincidental "cluster of vanishings," they also could include incidents of foul play. UFOs or Bigfoot are probably not involved, despite some local folklore.

• Crime: Abduction
• Year: 1930

The 41-year-old New York Supreme Court justice vanished on the evening of Aug. 6 after leaving a Midtown Manhattan steakhouse on his way to see a Broadway play. Because of his role as an arbiter of justice during the Prohibition Era in a major U.S. city, Crater almost certainly had enemies, but neither his body nor any suspects ever emerged.

For some time after his high-profile disappearance, the term "pulling a Crater" was used to describe someone leaving a social gathering unannounced.

• Crime: Abduction
• Year: 1945

A fire erupted in a house on Christmas Eve in Fayetteville, West Virginia, in which four of nine children escaped the flames. What happened to the other five children, whose remains were never found, is a mystery, but speculation was that they had been abducted.

Some witnesses said they later saw the children alive, and 20 years after the fire, the mother of the children received a photo in the mail of a man labeled Louis Sodder, one of the five missing children, who was 9 years old at the time. The local fire chief said that the fire burned hot enough to completely cremate the children, but this claim is disputed by many fire experts.

• Crime: Murder
• Year: 1947

As with many cases today involving women who are victims of male violence, the horrific murder and dismemberment of this 22-year-old aspiring Los Angeles actress focused on Short's loose reputation and history of underage drinking and the way she dressed.

Short posthumously earned the nickname "Black Dahlia", which likely came from press sensationalism. The name also alluded to the 1946 film "Blue Dahlia" about the murder of an unfaithful wife. No suspect was ever caught and the case eventually went cold.

• Crime: Murder
• Year: 1947

The mobster who was instrumental in developing the Las Vegas Strip was gunned down in Beverly Hills on June 20. It's widely believed mob boss Meyer Lansky ordered the hit because Siegel was spending too much of Lansky's money to develop the Strip's Flamingo Hotel.

In 2014, the widow of truck driver Mathew "Moose" Pandza claimed that her late husband murdered Siegel over a love affair Moose was having with the wife of Siegel's best friend and business partner, but the case has yet to be solved.

• Crime: Murder
• Year: 1956

The bodies of the Chicago sisters, ages 13 and 15, were found on a country road a month after their disappearance. Investigators initially focused on a "local drifter" but he was never formally charged. In what could be considered a 1950s version of media "clickbait," journalists exploited the fact the sisters had gone to see the newly released Elvis Presley film "Love Me Tender" to give the story traction.

This superficial link to Elvis led to wild speculation that the girls had secret lovers, or they ran away to Presley's hometown of Memphis hoping to meet the rock 'n roll star. As with a viral fad on TikTok, people lost interest and the case went cold.

• Crime: Jailbreak
• Year: 1962

The famous island prison a little over a mile off the coast of San Francisco shut down in 1963 due to cost concerns. Today, "The Rock," as it was known by inmates and prison guards, is part of the National Park Service. For nearly 30 years, it held prisoners including gangsters Al Capone and George "Machine Gun" Kelly.

Among other famous inmates, brothers John and Clarence Anglin and Frank Morris were prisoners at Alcatraz. In 1962, they executed an elaborate escape plan using three papier-mâché heads that made them appear to be sleeping as they chiseled through cell wall vent holes to a utility corridor.

One possible scenario is that the men drowned and their bodies were swept to sea, but the U.S. Marshals Service has kept the case open "in the unlikely event the trio is still alive," according to the FBI.

• Crime: Murder
• Year: 1965

Officially, Kilgallen's New York City death certificate says the co-host of the popular game show "What's My Line?" died from a deadly mix of alcohol and barbiturates, adding that the circumstances are "undetermined." But speculation abounded after her death about those circumstances.

Was it an accidental overdose? Suicide? Or was it, as some people claimed, a disguised murder? Adding to the speculation was a 911 call around the time of her death claiming Kilgallen had indeed been murdered. Investigators neither identified a suspect nor resolved the case.

• Crime: Zodiac serial killings
• Year: 1968-69

One of the biggest unsolved serial murder cases revolves around the "Zodiac Killer," an unidentified Northern California murderer who used the nickname to conceal his identity in hand-written encrypted letters he sent to the police and the local media.

Though he may have murdered 37 people in the 1960s and 1970s, a feat that would make him a serial killer Hall-of-Famer, investigators linked him positively to only five murders and two attempted killings in which targets managed to escape.

On Oct. 6, 2021, a group of independent investigators claimed to have identified the killer as Air Force veteran and gang leader Gary Francis Poste, who died in 2018. The San Francisco police, however, still consider these murders unsolved.

• Year: 1971

One of the most famous heists in history occurred on Nov. 24, 1971, when a man who identified himself as Dan Cooper (also known as D.B.) bought a one-way ticket to Seattle on Northwest Orient Airlines from Portland, Oregon. During the flight, he used a fake suitcase bomb to ransom passengers in return for $200,000 and four parachutes, to be delivered to him as the plane was parked on the tarmac in Seattle.

He then demanded pilots take him to Mexico City, but somewhere between Seattle and Reno, he jumped from the plane with the money. In 1980, a boy found a package with $5,800 in rotting $20 bills. The currency serial numbers identified that cash as part of the ransom, but Cooper was never found. The FBI suspended active investigation in 2016, but they say the case remains an "intriguing mystery."

• Year: 1975

The infamous Teamster had plenty of enemies considering his mob ties and the fact that he served time for jury tampering, mail fraud, and bribery. But his fate remains one of the most enduring criminal mysteries. Hoffa was last seen in the parking lot of a Michigan restaurant in 1975 and officials declared him dead in 1982 despite never discovering his body.

The only evidence was a length of hair found in a car connected to associate Charles "Chuckie" O'Brien. The hair was matched to Hoffa years later via mitochondrial DNA. The quest to find Hoffa's remains continued into the 2000s when the FBI searched, unsuccessfully, beneath a Detroit swimming pool in 2003 and beneath the floorboards of another Motor City property the following year.

• Year: 1978

Crane is best known for his role as Col. Robert H. Hogan of the 1960s TV sitcom "Hogan's Heroes," about a group of American POWs in Nazi Germany. He's also known to be what the Associated Press called a "skirt-chasing actor" who filmed himself having sex with women.

When he was found dead in a Scottsdale, Arizona, apartment from blunt-force trauma with an electrical cord wrapped around his neck, the primary suspect emerged as John Henry Carpenter, an electronics salesman who helped produce and act in Crane's amateur films.

Blood with Crane's blood type was found in Carpenter's vehicle, but a lack of DNA testing at the time led to insufficient evidence and Carpenter's acquittal in 1994, four years before he died.

• Year: 1982

A man, his pregnant wife, their two children, and four fishing boat deckhands in the small southeastern village of Craig were fatally shot in a boat on Sept. 6 in the worst unsolved multiple homicide in Alaska's history. After the bloodbath, the killer piloted the 58-foot boat to a nearby secluded bay, waving at a nearby skipper as he departed.

For unknown reasons, the killer then returned the vessel on the following day and torched the craft using gasoline as an accelerant before fleeing the scene and the village. Investigators were only able to determine that the suspect was a white man in his 20s with a pockmarked complexion.

• Year: 1982

Seven Chicago-area people were murdered in the infamous Tylenol poisoning incident. Bottles of the popular pain and fever reliever were spiked with cyanide and returned to store shelves, targeting random people. The poisonings led to the creation of tamper-proof packaging regulations in the U.S.

The case remains unsolved, but in January 2023, CBS Chicago reported that it had obtained documents through a Freedom of Information Act request showing investigators looked into the DNA of a woman and her late father whose fingerprints were found on a bottle of the tainted medicine.

Investigators said the DNA testing was to eliminate suspects, but they would not comment further on what prompted them to conduct the tests nearly 30 years after the crime.

• Year: 1990

In a heist worthy of a crime thriller, unknown men posing as police officers investigating a disturbance at the Boston-based art museum stole works of art by Degas, Manet, Rembrandt, Vermeer, and other masters so renowned that their full names are unnecessary.

According to Boston Globe reporter Stephen Kurkjian, the value of the paintings could be $500 million or more, but he added that they are unsellable in any legitimate art market. This adds to the mystery of the case because the motive for the unsolved crime remains unclear.

Today, visitors to the museum can still see the empty frames where the paintings once hung.

• Year: 1994

A joke emerged after the infamous double-murder trial of O.J. Simpson in the mid-'90s that "The Los Angeles Police Department has framed a guilty man." It refers to what many believe to have been a cut-and-dried case in which the pro-football hall of famer murdered his ex-wife and her friend in a jealous rage on June 12, 1994.

Though Simpson's defense argued that LAPD detective Mark Fuhrman, a key investigator in the double homicide, was a racist, they never directly accused him of planting a bloody glove as evidence at the crime scene.

The trial, which exposed deep racial divisions about the U.S. justice system's treatment of Black Americans, ended with O.J.'s acquittal. Officially, the case remains unsolved.

• Year: 1996

The 9-year-old girl was abducted while riding her bike in a grocery store parking lot in Arlington, Texas. People discovered her body nearby five days later showing signs of sexual assault. In what would have been a random tragedy, another soon-to-be-forgotten unsolved abduction and murder case ended up having at least one positive outcome.

The case led to the creation of the "Amber Alert" early-warning child-abduction system. The Department of Justice says that as of January 2023, the nation's 82 Amber Alert programs have led to the rescue of more than 1,127 children. Unfortunately, Amber Hagerman's abductor and killer was never found.

• Year: 1996

The six-year-old beauty pageant winner was found dead in the basement of her Boulder, Colorado, home a day after Christmas in a case that captured national attention. The circumstances that led to Ramsey's murder remain a matter of speculation. The coroner listed asphyxia by strangulation associated with craniocerebral trauma. Evidence consistent with sexual assault was reported, but interpretations remain disputed.

Suspects included Ramsey's parents, her nine-year-old brother, a family friend who had dressed like Santa Claus at a recent family party, and a random unknown intruder. Investigators botched their job by allowing supporters who arrived shortly after police response to wander around the crime scene, including some who helped to clean up the kitchen before an evidence sweep had been completed.

• Year: 1997

Christopher "Notorious B.I.G." Wallace, 24, was murdered by four gunshots in a drive-by shooting. Wallace was leaving a Soul Train Awards after-party at Petersen Automotive Museum in Los Angeles just after midnight on March 9 when he was gunned down. The New York City-born rapper was murdered six months after Tupac Shakur died following a drive-by shooting in Las Vegas.

Both Tupac and Biggie Smalls, as Wallace was also known, were both born in New York City and were central to the East Coast hip-hop scene. Conspiracy theories claim Wallace plotted the killing of Tupac over a dispute. Others suggest both rappers were murdered by West Coast gang members over petty differences.