HLN

A cunning serial rapist who leaves no decisive evidence forces investigators to rely on geographical profiling in their search for an identity; DNA from a cigarette butt may provide the final piece of evidence needed to catch the suspect.

New evidence including fibers and weather patterns point to a different killer in the 1986 case of a Pennsylvania dentist's murdered wife.

Insects and a single strand of hair uncover an additional suspect in the killing of a young mother and her baby in Lehigh Valley, Pa.

A decomposed body is found in a barrel, and a dilapidated address book may hold the answer, but investigators must find a way to read the pages because the passage of 30 years has turned them blank.

When a policeman's home burns to the ground, he later arrests a man who confesses to arson, but the confession seems dubious.

A woman identifies her husband as her attacker, but questions arise 16 years later regarding her recollections.

When a young doctor is accused of sedating and sexually assaulting two of his female patients, DNA tests show him to be innocent, but the women persist with their claims; seven years later, a private investigation leads to a surprising discovery.

The search for the killer of two teenagers in Texas shows a behavioral study on how most serial killers also have a history of abusing animals.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

Although a group of teenage thugs are suspected of attacking two boys on a fishing trip, there is no solid evidence until a murky fishing hole provides some answers.

When young prostitute's body turns up in an Ohio waterway, authorities have one tiny clue which could point to her killer, but face huge challenges due to her policemen clients and DNA evidence being washed away.

In a small South Carolina town in 1991, 17-year-old Crystal Faye Todd, a popular high school student, is raped, murdered and dumped in a deserted field; with few leads, authorities test the DNA of several friends, and one match shocks everyone.

In a groundbreaking case using animal DNA, investigators use forensic testing on a cat to help them solve the case of a woman who vanished from her home on Prince Edward Island.

A look into the 1984 Oregon food poisonings, where detectives track down the outbreak to a cult which aims to use germ warfare to take down the government.

A woman is found dead from a gunshot wound and police suspect her husband, however, forensic teams prove what really happened, and the truth is stranger than fiction.

After American Atheists founder Madalyn Murray O'Hair disappears, the discovery of a mutilated body helps police catch the culprit.

Two people witness a truck driving over an unconscious man and flee into a nearby bar, but when the police turn up, the truck, the man and the witnesses are gone.

Insect evidence helps to solve the mystery of a woman found dead near a river bank.

A girl who is abducted and then released soon afterward uses her knowledge of forensics to lead police to the kidnapper.

A trash collector finds a severed human leg in a trash bin, but police cannot use conventional methods of victim identification; investigators turn to toxicology and DNA tests to find the murder-mutilator.

A coroner finds telltale clues on the badly burned body of a murder victim, sending police in pursuit of a couple of killers.

A young girl is found dead, the victim of an apparent sex killer; there are few clues to the killer's identity, but authorities are intrigued by unusual orange fibers embedded in clothing found near the victim.

Police charge Alan "The Zenith Man" Ridley with murdering his wife, Virginia, but following an autopsy, medical detectives believe he may not have killed his wife after all.

With children dying at an alarming rate at a Texas hospital, authorities narrow down their probe to one nurse, but the murder weapon remains elusive.

When the decomposed body of a young girl is discovered, police have no clues to her identity, but days earlier, a stabbing victim told them she thought she might have witnessed a murder.

When a doctor's wife disappears, investigators use concrete from the doctor's yard and the recollections of a child to determine what happened.

Romanian archbishop Valerian D. Trifa, living in the U.S., is accused of being a Nazi war criminal, and forensic experts find evidence on an incriminating, 40-year-old postcard.

Investigators look into the shooting death of Russ Stager, a popular gym teacher, and discover that his death was not an accident; a message the victim recorded before his death reveals a story of greed.

A money launderer is found dead in the ocean and the only obvious clues to his identity are a Rolex watch and a tattoo; the anchor with which he is weighed down proves most helpful in solving the crime.

The apparent suicide of Dr. Darryl Sutorius, a respected heart surgeon, is questioned when an investigation reveals his new wife's violent history.

The 1992 hit-and-run death of 6-year-old Nicole Rae Walker leads to a groundbreaking trial as experts submit a video reconstruction of the incident, implicating a drunk driver and demonstrating the viability of video testimony.

Specialists including a NASA vendor help police reconstruct a damaged surveillance video to catch the murderer of convenience store employee Wanda Mason in Lansing, Mich.

When a young woman goes missing, the police investigation reveals that she led a double life -- student by day, call-girl by night -- but when her body is discovered, even more strange truths are uncovered.

A tiny clue inside a suspect's watchband and a popular television show help solve the case of a woman's disappearance.

One year after Maine resident Pearl A. Bruns' disappearance, forensic technology helps to find her body and determine who was responsible for her death.

When 4-year-old April Renee Tucker is found dead in her backyard, her parents tell the police that neighborhood dogs attacked and killed her, but the injuries on her body don't match their account of what happened.

San Diego police investigate the murder of a missing person whose hands turn up in a dumpster; an anonymous letter, containing details only the killer would know, offers clues to solving the case.

One year after her father's death, a teen's role in a high school production of "Hamlet" causes her to reveal the chilling truth behind her family's tragedy.

A mother puts her hope on the internet and an independent investigation to clear her name after authorities charge her with murdering her 17-month-old son in a fire considered to be intentionally set.

When a man dies unexpectedly in the office of a noted California doctor, police begin what they think will be a routine investigation, but discoveries of false identities and insurance fraud raise questions about the doctor's role.

A forensic scientist uses his skills to preserve a footprint left in snow to help authorities nab two men suspected of robbing an Ontario couple and shooting the husband in the head.

Fingerprints taken from a piece of cloth help solve the rape and murder of a 22-year-old woman in Henrico County, Va.

The FBI profiles a suspect in the kidnapping and murder of a 6-year-old girl during an evening church service; a witness leads authorities to the likely killer, but then becomes a victim herself.

Photographs found in a dumpster lead to the killer of Los Angeles model Linda Sobek; the man claims he did not intentionally kill her despite evidence to the contrary.

A murder mystery theater performance in Easton, Md., turns into a real-life mystery when a body is found after the performance ends.

When a woman dies in a horseback riding accident, police uncover a web of lies in her husband's background after his suspicious behavior prompts a closer look.

A serial killer in Tampa, Fla., taunts police by strangling prostitutes and leaving their bodies in plain sight, but tire marks and fibers lead to the culprit.

Missouri police are thrust into a bizarre web of homeless drifters and cattle auctions when they are called to retrieve a dead body.

A killer wants to outwit the police and keep the identity of his victim secret so he removes the teeth; however, lab tests on the skull reveal not just the horrific nature of the murder, but the identity of the victim too.

When a farmer's wife disappears, the tests of a plant pathologist and a dendrochronologist lead to a surprising revelation.

A son who is convinced of his mother's innocence in the death of his father enrolls in law school to try and clear her name.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

A man is arrested and convicted for a series of sexual assaults in Indiana; years later, forensic developments reveal new facts about the case.

The murder of a young Seattle couple puzzles investigators until the victims' dog, Chief, leads police to the killer.

A handsome young doctor's fiancée experiences severe illness after revealing that she is pregnant, and launches her own investigation to determine if the doctor is somehow responsible.

When prison guard Donna Payant's body is discovered at a landfill, a medical examiner uses a "signature" clue to link her death to a murder the same examiner investigated 10 years earlier.

When a 9-year-old girl vanishes on her way to school, the entire community helps with the search; detectives believe her mother may be involved, and a hidden fingerprint seals the case.

The investigation of a murder case in New Jersey is stalled until a similar attack occurs on a state trooper in Maine.

A young woman goes missing without leaving many clues, but the advanced technology on offer makes it possible for cat hairs and insects to help build an image of the abductor.

Blood spatter analysis and an investigation lead police to the truth when a pregnant woman is found dead in her home.

A mother is determined to discover what happened when her daughter is injured in a hit-and-run accident.

Forensic science and deductive reasoning determine what happened to a mother and daughter while they were on a shopping spree.

Exploring how an American hit single from 1966 -- "The Cheater" by Bob Kuban and the In-Men -- foreshadowed the demise of the group's lead singer, Walter Scott.

Eight years after a man confessed to the murder of a young woman, another man claims that he committed the crime, and investigators must use forensic evidence to determine the true killer.

Although a group of teenage thugs are suspected of attacking two boys on a fishing trip, there is no solid evidence until a murky fishing hole provides some answers.

When young prostitute's body turns up in an Ohio waterway, authorities have one tiny clue which could point to her killer, but face huge challenges due to her policemen clients and DNA evidence being washed away.

In a small South Carolina town in 1991, 17-year-old Crystal Faye Todd, a popular high school student, is raped, murdered and dumped in a deserted field; with few leads, authorities test the DNA of several friends, and one match shocks everyone.