The murders of two young women near a Phoenix canal remain unsolved for more than 20 years until a team of cold case detectives take on the case and investigate a man known as the Zombie Hunter.

California police in 1957 search for a murderer, but the case goes cold; 50 years after a crime is committed, advances in computer technology determine the killer.

Investigators piece together tiny clues at the scene of a hit-and-run accident; their findings help to track down the offending driver.

Investigators determine what caused a house fire that killed an elderly couple and whether the victims' son is responsible.

Detectives are suspicious after a woman is killed in a hunting accident, but it takes more than twenty years before a trace evidence analyst is able to match fibers on a soiled blanket to the killer.

It was a violent and bizarre crime scene: #1 scrawled next to the lifeless body; the victim's boyfriend had an alibi and the case went cold; then, a DNA hit; but investigators couldn't figure out the link between two people separated by 1,500 miles.

When hunters find a skull in a Texas canyon, police find bits of clothing, a woman's shoe, some small bones and a strand of hair; once they discover her identity, it was time to find the killer.

A wife is missing in Key West; investigators wonder if they should be searching for a missing person or a killer.

When a beloved socialite in the suburbs of New York is an unlikely target for a brutal murder, police immediately zero in on the most likely suspect, but solving the crime is neither easy nor quick.

Suicide notes and a pistol in hand lead police to suspect that a mother of two young children appeared to had killed herself, but when investigators learned of a house fire she was in three years earlier, they reinvestigate.

The violent death of an Air Force officer's wife outside a Philippines air base is examined, amid accusations of a love triangle involving the murdered woman's husband; investigators use groundbreaking computer forensics to make their case.

A woman is brutally murdered in her bed; her husband and son both immediately begin pointing fingers at each other after two rapid fire calls are made to 911.

Pieces of plastic the size of sand hold clues to a bombing.

At first glance it appears a young woman suffocated, but further investigation shows the scene was staged.

Chaos descends on Phoenix as two serial killers compete for the media's attention and the bodies pile up faster than the police can investigate.

A killer is careless when a home is destroyed by fire and a young boy is missing.

A patrol officer is shocked by the amount of blood at a traffic accident and is shocked by the coroner's ruling until an anonymous phone call re-ignites the case.

An irrigation canal murder remains unsolved until a similar murder occurs.

The light of day and DNA picture painted by molecular biologist reveals new clues about a nighttime traffic accident.

In the California mountains, a young father calls 911 to report that he had been in a shoot-out with a car full of strangers; authorities wonder if it was self-defense or something else.

In the California mountains, a young father calls 911 to report that he had been in a shoot-out with a car full of strangers; authorities wonder if it was self-defense or something else.

In 1994, convicted murderer Randolph Dial escapes from a prison in Oklahoma and takes the deputy warden's wife, Bobbi Parker, with him, then, 10 years later, Parker is found living with Dial on a farm in Texas.

A wealthy Miami couple disappears, leaving an abandoned Lamborghini; police are perplexed until a rich businessman comes forward with a bizarre tale of a group of muscled men looking for a fast way to flashy cars and a fabulous lifestyle.

Chilling confessions from a vicious slasher detail only some of his 100+ victims; when he's set to be the first serial killer ever released from prison, an eyewitness from decades prior could force justice on the man who vows to kill again.

Young newlyweds Michael and Susan MacIvor were living the dream in the Florida Keys with a baby on the way; the Florida Man strikes in paradise; under the cover of a storm, the MacIvors become victims of a triple homicide.

In the '90s, aderanged killer stalks sex workers in Riverside, Calif., claiming the lives of 13 women; when a would-be victim describes the perp to police, the race is on to catch the murderous john before he strikes again.

Investigators from three separate counties along the Floribama border team up with the daughter of a missing man to uncover how the fireworks at a Fourth of July celebration ended in murder.

Five corpses are found on the Florida hog trails; the investigation stalls until two men narrowly escape the perp's clutches; years later, eight more bodies are found in nearby woods, leaving police to wonder if it's the same evil killer.

The owners of an Alabama country store are brutally murdered in their home, and detectives must sort through a maze of bootlegging, gambling and family secrets to uncover the killer.

Multiple unidentified bodies are found inside barrels in a New Hampshire forest; decades later, a murder 3,000 miles away reveals their connection to a serial predator who targets women and children, and changes his identity after every violent kill.

After Hurricane Ivan tears through the Floribama region, the discovery of a body in a burnt-out home in Chunchula, Alabama, launches an investigation that reveals an unexpected evil in the community.

The deadly beating of a young man in West Liberty, Iowa, sits unsolved for 25 years, until cold case detectives are approached by an unexpected witness.

An investigation into the disappearance of a devoted father leads Arkansas police to a shocking crime scene, the search for answers reveals gang threats, and a killer that's willing to go to great lengths to escape justice.

When a beloved man is murdered on Mississippi's Gulf Coast, the slippery killer keeps police on their toes in a wild manhunt; investigators stop at nothing to uncover this twisted trail of lies and fraud as they work to bring some southern justice.

A former ladies' man has a change of heart when he falls for a pious day care worker, but when his body is found floating in a creek, detectives discover there's more to their relationship than meets the eye.

Amid the chaos of post-Hurricane Katrina, a devout pastor is mysteriously murdered in New Orleans; a second unsolved murder with the same signature leads investigators to a brazen killer weaving a deadly web.

The American dream of a hard-working immigrant is cut short when he is violently murdered with a hatchet in the streets of a Las Vegas suburb; investigators sift through lies and follow a bloody trail to uncover the shocking truth.

Frank Rodriguez, a Navy veteran who dedicated his life to helping needy children, is mysteriously murdered, and investigators need to figure out how he died to catch his killer.

An investigation into the murder of a New York businessman zeroes in on a family member whose plush lifestyle launches a tabloid frenzy; a closer look reveals the suspect's inner demons calling the greedy motive into question.

Eric Somuah, an outgoing salesman, is found shot in his bed; a detective's investigation of Eric's murder puts him on a path filled with twists, turns and an ending few will see coming.

The life of a married father of two and successful real estate appraiser ends all too soon; investigators wonder if money is a motive, or if the murder is the result of a family rift.

Sabrina admits to killing Lisa, but no one understands why, which complicates the case immensely.

A successful, seemingly healthy doctor collapses at home and is rushed to the ER, leaving friends and colleagues puzzled.

Jen Ramsaran vanished just before Christmas and detectives needed to know if her online life held the key to this mystery or if the answer was closer to home.

Investigators go to unexpected depths to solve the mystery of missing Lynn Friend, a devoted mother who had wedding plans when she vanished.

The murders of two young women near a Phoenix canal remain unsolved for more than 20 years until a team of cold case detectives take on the case and investigate a man known as the Zombie Hunter.

It was a violent and bizarre crime scene: #1 scrawled next to the lifeless body; the victim's boyfriend had an alibi and the case went cold; then, a DNA hit; but investigators couldn't figure out the link between two people separated by 1,500 miles.

When a beloved socialite in the suburbs of New York is an unlikely target for a brutal murder, police immediately zero in on the most likely suspect, but solving the crime is neither easy nor quick.

A woman is brutally murdered in her bed; her husband and son both immediately begin pointing fingers at each other after two rapid fire calls are made to 911.

Chaos descends on Phoenix as two serial killers compete for the media's attention and the bodies pile up faster than the police can investigate.

After multiple men are discovered brutally murdered, investigators determine that each victim was last seen with a handsome stranger they met in a bar.

When a model and up-and-coming YouTube celebrity turns up dead, police question her husband in the hope he can shed some light on the situation.

When a model and up-and-coming YouTube celebrity turns up dead, police question her husband in the hope he can shed some light on the situation.

A risky undercover operation in a rough prison could expose a suspected serial killer's secrets.

Chilling confessions from a vicious slasher detail only some of his 100+ victims; when he's set to be the first serial killer ever released from prison, an eyewitness from decades prior could force justice on the man who vows to kill again.

In the '90s, aderanged killer stalks sex workers in Riverside, Calif., claiming the lives of 13 women; when a would-be victim describes the perp to police, the race is on to catch the murderous john before he strikes again.

Five corpses are found on the Florida hog trails; the investigation stalls until two men narrowly escape the perp's clutches; years later, eight more bodies are found in nearby woods, leaving police to wonder if it's the same evil killer.

Multiple unidentified bodies are found inside barrels in a New Hampshire forest; decades later, a murder 3,000 miles away reveals their connection to a serial predator who targets women and children, and changes his identity after every violent kill.

The deadly beating of a young man in West Liberty, Iowa, sits unsolved for 25 years, until cold case detectives are approached by an unexpected witness.

An investigation into the disappearance of a devoted father leads Arkansas police to a shocking crime scene, the search for answers reveals gang threats, and a killer that's willing to go to great lengths to escape justice.

A former ladies' man has a change of heart when he falls for a pious day care worker, but when his body is found floating in a creek, detectives discover there's more to their relationship than meets the eye.

The American dream of a hard-working immigrant is cut short when he is violently murdered with a hatchet in the streets of a Las Vegas suburb; investigators sift through lies and follow a bloody trail to uncover the shocking truth.

An investigation into the murder of a New York businessman zeroes in on a family member whose plush lifestyle launches a tabloid frenzy; a closer look reveals the suspect's inner demons calling the greedy motive into question.

Baby Savanna disappears in the midst of a custody battle, and mystery of her whereabouts spans two decades; investigators traveled nearly 10,000 miles around the world, driven by a determined dad trying to learn what happened to his daughter.

People went on a hike, pausing at a perfect spot for pictures; but something went wrong, and the frigid currents below took a life; investigators wondered if they also swept away a secret.

Diane Marcell walked into her home and found her daughter covered in blood, the attacker said she was next; a single drop of blood was the key to finding him, but it took nearly a decade to unlock its secrets.

Single mom Sarah Goode went missing after a night out with friends; her family was determined to find her; police turned up four possible suspects and two tantalizing clues; the killer left a signature.

After Erin Corwin told her husband she was scouting hiking trails in Joshua Tree National Park, she suddenly vanished -- police quickly uncovered a steamy love triangle and a mystery with a deep pool of potential suspects.

He was a wealthy doctor with a perfect life and the perfect wife; then, he found her dead on Valentine's Day; she was beloved but did have enemies; investigators followed a bloody trail of evidence, leading to a big courtroom twist.

A killer is murdering and mutilating young women along the Route 40 corridor in Delaware, but after investigators set up an undercover operation, the hunter soon becomes the hunted.

After multiple men are discovered brutally murdered, investigators determine that each victim was last seen with a handsome stranger they met in a bar.

A pilot flees following a plane crash, becomes a fugitive and lives a double life for decades.

A pilot flees following a plane crash, becomes a fugitive and lives a double life for decades.

The legendary Fontainebleau Hotel in Miami Beach, Fla., is the backdrop for a mystery involving the murders of wealthy heir Ben Novack and his mother, Bernice.

A couple's anniversary celebration ends in murder during what appears to have been a home invasion, but investigators believe the suspect might be connected to the victim.

A woman accused of attempting to hire a hit man to kill her husband.

When a woman's body is discovered at a trash facility, a detective makes a promise to her mother to get justice; she doesn't know she will come face to face with a serial killer.

A group of adventurous Americans think they found paradise in a tropical hideaway, the kind of place where people don't ask a lot of questions about their neighbors, until some of those neighbors start to disappear.

New interviews with insiders reveal how career criminal Charles Manson convinced his followers to kill innocent victims and deliver him the fame he craved.

Spree killer Joanne Dennehy's daughter Shianne shares how she has struggled to come to terms with the realities of being the child of Britain's most dangerous woman.

Peter Tobin raped and murdered Angelika Kluk in 2006, and with the help of his ex-wife, Cathy Wilson, a groundbreaking investigation unearthed more victims and revealed him to be a serial killer.

Inside the mind of America's most notorious serial killer, Jeffrey Dahmer; new revelations and never-before-seen interviews shed light on the grizzly and twisted case, told firsthand from those closest to Dahmer, including family.

Diving inside the mind of New York's most prolific serial killer, Joel Rifkin; through never-before-heard interviews from Attica Correctional Facility, Joel Rifkin reveals exclusive insights into the mind of a monster.

Kelly and her team investigate the murder of a college student killed in her bedroom while packing for a trip to visit her parents for Thanksgiving.

Kelly and Steve Spingola take on a case in his home state of Wisconsin and must navigate a tangled family tree of witnesses and suspects to find the killer of a loving husband fatally shot in his cabin.

Kelly and Steve Spingola head to Flint, Mich. to investigate the brazen 1991 shooting of a beloved woman right outside her home; as she died in her sister's arms, her final words could provide insight into who killed her.

Kelly and Aaron Sam head to Lake Charles, La., to investigate the shocking murder of a young man gunned down in his car after attending church on Palm Sunday.

Kelly and Steve Spingola head to Wisconsin to investigate a homicide; the case becomes personal after they receive a letter from the victim's daughters; their search uncovers a town's dark side, crimes against children and lies within a church.

Former FBI Special Agent John Douglas and psychiatrist Louis Schlesinger take a deep dive into serial killer Edmund Kemper's troubled history, intellect and evolution; the groundbreaking FBI work that led to breakthroughs in catching serial killers.

After a decadeslong crime spree terrorizes California, a DNA breakthrough leads detectives to a suspect in one of the most famous cases in history; Stephanie Gosk and detective Paul Holes trace the life of suspect Joe DeAngelo.

Brittany Stork's decades-long quest to find out more about her mother's mysterious death leads to a dramatic courtroom decision; the man at the center of the case tells his side of the story.

Brittany Stork's decades-long quest to find out more about her mother's mysterious death leads to a dramatic courtroom decision; the man at the center of the case tells his side of the story.

A luxury car salesman is asked by a beautiful former client to plan a murder.

A couple's anniversary celebration ends in murder during what appears to have been a home invasion, but investigators believe the suspect might be connected to the victim.

A woman accused of attempting to hire a hit man to kill her husband.

When a woman's body is discovered at a trash facility, a detective makes a promise to her mother to get justice; she doesn't know she will come face to face with a serial killer.

An in-depth look at the complexities of the case against Aileen Wuornos, the woman branded as America's first female serial killer; questions still revolve around her claim of self-defense and whether or not she got the justice she deserved.

A group of adventurous Americans think they found paradise in a tropical hideaway, the kind of place where people don't ask a lot of questions about their neighbors, until some of those neighbors start to disappear.

New interviews with insiders reveal how career criminal Charles Manson convinced his followers to kill innocent victims and deliver him the fame he craved.

The man known as the Happy Face Killer viciously strangled eight women and dumped their bodies along the road.

Spree killer Joanne Dennehy's daughter Shianne shares how she has struggled to come to terms with the realities of being the child of Britain's most dangerous woman.

The stories of five women who suffered vile abuse while trapped inside the home of a prolific serial killer from which they eventually escaped.

Peter Tobin raped and murdered Angelika Kluk in 2006, and with the help of his ex-wife, Cathy Wilson, a groundbreaking investigation unearthed more victims and revealed him to be a serial killer.

Inside the mind of America's most notorious serial killer, Jeffrey Dahmer; new revelations and never-before-seen interviews shed light on the grizzly and twisted case, told firsthand from those closest to Dahmer, including family.

Self-named killer B.T.K. murders 10 people over 17 years, all while taunting Wichita, Kan., police and media before being exposed as family man and churchgoer Dennis Rader; in an exclusively acquired interview, he reveals what drove him to do it.

Diving inside the mind of New York's most prolific serial killer, Joel Rifkin; through never-before-heard interviews from Attica Correctional Facility, Joel Rifkin reveals exclusive insights into the mind of a monster.

In the 1970s, Ted Bundy murders at least 36 young women; glamorized as a handsome, well-educated killer who outsmarted the law, Bundy may have been an evil genius or a con artist posing as privileged to hide the monster in plain sight.

Kelly and her team investigate the murder of a college student killed in her bedroom while packing for a trip to visit her parents for Thanksgiving.

When searching for a missing woman, law enforcement on Long Island stumble upon the remains of other victims; as the killer of the so-called "Gilgo Four" remains elusive, police come to believe that the monster himself may live among them.

Kelly and Steve Spingola take on a case in his home state of Wisconsin and must navigate a tangled family tree of witnesses and suspects to find the killer of a loving husband fatally shot in his cabin.

After Rex Heuermann is arrested and charged as the Gilgo Beach killer, a feverish hunt for information is undertaken -- but his family isn't talking; now, for the first time, the loved ones of the alleged killer speak publicly.

Kelly and Steve Spingola head to Flint, Mich. to investigate the brazen 1991 shooting of a beloved woman right outside her home; as she died in her sister's arms, her final words could provide insight into who killed her.

From 1993 to 2000, the quiet community of Fort Smith, Ark., is terrorized by a twisted serial killer, a deranged necrophiliac who targets elderly and vulnerable women; he becomes known as The River Valley Killer.

Kelly and Aaron Sam head to Lake Charles, La., to investigate the shocking murder of a young man gunned down in his car after attending church on Palm Sunday.

Kelly and Steve Spingola head to Wisconsin to investigate a homicide; the case becomes personal after they receive a letter from the victim's daughters; their search uncovers a town's dark side, crimes against children and lies within a church.

Colleen Stan relives what it was like to be kidnapped and imprisoned in a box, and how she escaped.

Former FBI Special Agent John Douglas and psychiatrist Louis Schlesinger take a deep dive into serial killer Edmund Kemper's troubled history, intellect and evolution; the groundbreaking FBI work that led to breakthroughs in catching serial killers.

An examination into whether Ted Bundy, glamorized as a handsome, well-educated killer who outsmarted the law, was really an evil genius or a con artist posing as privileged to hide the monster in plain sight.

After a decadeslong crime spree terrorizes California, a DNA breakthrough leads detectives to a suspect in one of the most famous cases in history; Stephanie Gosk and detective Paul Holes trace the life of suspect Joe DeAngelo.

On Valentine's Day, an obstetrician finds his wife dead and calls 911; police discover inconsistencies between the blood spatter evidence and his version of events.

Brittany Stork's decades-long quest to find out more about her mother's mysterious death leads to a dramatic courtroom decision; the man at the center of the case tells his side of the story.

Brittany Stork's decades-long quest to find out more about her mother's mysterious death leads to a dramatic courtroom decision; the man at the center of the case tells his side of the story.

A luxury car salesman is asked by a beautiful former client to plan a murder.

When film executive Gavin Smith vanishes, Los Angeles detectives search for clues amid reported sightings and suspicious circumstances.

An investigation of a woman found murdered in Fort Worth, Texas.

An in-depth look at the complexities of the case against Aileen Wuornos, the woman branded as America's first female serial killer; questions still revolve around her claim of self-defense and whether or not she got the justice she deserved.

The man known as the Happy Face Killer viciously strangled eight women and dumped their bodies along the road.

The stories of five women who suffered vile abuse while trapped inside the home of a prolific serial killer from which they eventually escaped.

Self-named killer B.T.K. murders 10 people over 17 years, all while taunting Wichita, Kan., police and media before being exposed as family man and churchgoer Dennis Rader; in an exclusively acquired interview, he reveals what drove him to do it.

In the 1970s, Ted Bundy murders at least 36 young women; glamorized as a handsome, well-educated killer who outsmarted the law, Bundy may have been an evil genius or a con artist posing as privileged to hide the monster in plain sight.

When searching for a missing woman, law enforcement on Long Island stumble upon the remains of other victims; as the killer of the so-called "Gilgo Four" remains elusive, police come to believe that the monster himself may live among them.

After Rex Heuermann is arrested and charged as the Gilgo Beach killer, a feverish hunt for information is undertaken -- but his family isn't talking; now, for the first time, the loved ones of the alleged killer speak publicly.

From 1993 to 2000, the quiet community of Fort Smith, Ark., is terrorized by a twisted serial killer, a deranged necrophiliac who targets elderly and vulnerable women; he becomes known as The River Valley Killer.

Colleen Stan relives what it was like to be kidnapped and imprisoned in a box, and how she escaped.

An examination into whether Ted Bundy, glamorized as a handsome, well-educated killer who outsmarted the law, was really an evil genius or a con artist posing as privileged to hide the monster in plain sight.

On Valentine's Day, an obstetrician finds his wife dead and calls 911; police discover inconsistencies between the blood spatter evidence and his version of events.

A teen's murder shakes a Nevada community, especially when two unlikely people make confessions.

A teen's murder shakes a Nevada community, especially when two unlikely people make confessions.

The mysterious death of a young mother in Ohio and the ensuing investigation that spans years and multiple states.