In 1971, John List left a note with the bodies of his mother, wife, and three children in his mansion ballroom, funeral organ music blaring from a central sound system, and disappeared. Eighteen years later, all detectives had to work from is an outdated photograph of List. In 1989, the popular television series America's Most Wanted commissioned an age-scaled bust of List to aid viewers in identifying the confessed murderer. Dr. Frank Bender, nationally-recognized artist and sculptor, worked with forensic psychologist Richard Walter to develop a profile of the aging List.

In 1992, in a rural Canadian community, Dr. John Schneeberger 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; 7 years later, a private investigation leads to a surprising discovery.

Two people in Seattle, Washington died after taking an over-the-counter pain reliever; lab analysis of the pills showed they were tainted with a lethal concentration of cyanide. The investigation which followed led police to a suspect with a motive for murder and a callous disregard for others.

When a decomposed body is discovered inside a barrel, police immediately suspect foul play. But the body had been placed there 30 years earlier. One of the few clues was an address book found along with the body but years of moisture had washed away the ink. Scientists desperately searched for a way to unlock the secrets of that address book.

In 1994, a human skull found in an Ohio pond uncovers a ghastly crime. Markings on the skull indicate that the victim had been stabbed many times and that the teeth had been removed with needle-nose pliers in an attempt to keep the victim's identity a secret. Forensic scientists use DNA matches to indentify the skull.

A young man was killed in a mysterious car crash, but the evidence at the scene led investigators to believe it was not an accident. Forensic science revealed what really happened, and the truth devastated three families.

A 6-year-old girl ran and hid when she saw her grandmother being beaten to death, but the man followed her, beat her and assaulted her. The girl said he was her Uncle Clarence, and he was convicted because of her identification. She recanted her testimony years later, but the court denied Clarence's petition for a new trial. His wife was convinced he was innocent, and decided to conduct her own investigation to prove it.

In 1996, police received a call from Darlie Routier telling them of her two sons' murders. However, investigators were not certain about the validity of Darlie's story and began an intensive search of the crime scene. The police found out who the killer was by analyzing blood spatter, doing behavioral profiling and analyzing Darlie's 911 call.

When a sexual predator murders two young boys in Nebraska within three months of each other, an obscure style of rope and forensic analysis lead to his arrest and conviction.

Lori Keidel, her two sisters and her brother were left home alone while their father went to a nearby laundromat. Suddenly, a large fire engulfed their brick ranch home. Only a few months earlier, the children's mother had disappeared and made no effort to contact them. Lori found the courage to tell police that she had witnessed her own mother's death.

Two men were convicted of intentionally shooting and killing a passenger in a moving car, their friend was granted immunity for testifying against them, and the case was closed. Then a bomb exploded in the family home of the state's witness, instantly killing his father. Investigators turned to forensic science, hoping to determine if this was an act of revenge and if there was a way to link the two deadly crimes.

When the head chef of a historic Philadelphia restaurant was found dead, investigators interviewed the usual suspects: family, friends and coworkers. As they sifted through the evidence, police uncovered a chilling tale of debt and deceit.

The case of missing stewardess Helle Craft is recounted. Although her body was never recovered, police used forensic evidence to charge her husband with murder. It became the first murder conviction without a body in Connecticut.

The first case to use DNA evidence is detailed. In 1983 Leicester, England, police were stymied by a rape/murder of a 15-year-old girl; three years later, faced with a similar crime, they turned to Dr. Alec Jeffreys, a molecular biologist with a revolutionary approach to solving the case.

The year was 1984, and a serial killer was on the loose in Florida. Eight women had been found dead. At each crime scene, investigators found tiny red fibers, fibers they hoped would lead them to the killer.

The flu-like symptoms of a mother and her children proved to be indicative something much more serious: thallium poisoning. Investigators had to find the source of the poison... and when the mother died, to determine if the exposure was accidental, or if they also needed to find a killer.

Creating a “profile” of a serial killer is part science and part intuition. The science involves studying criminals who have committed similar crimes, to see what characteristics they have in common. In a search for the killer of two teenagers in Texas, a behavioral profile led to a possible suspect - and hard science proved the profile was correct; it shows a behavioral study on how most serial killers also have a history of abusing animals.

In 1957, California police searched for a man who had committed several crimes in one night – including murder, but after following thousands of leads, eventually, the case turns cold. Almost 50 years later, with advances in computer technology and handwriting analysis, investigators determine the killer.

Bombings are difficult to solve, because the perpetrator isn't usually at the scene, and the evidence goes up in smoke. But there are clues if investigators know where to look. In this case pieces of plastic the size of grains of sand, held the key to a man's murder.

When a fire destroyed most of a home and a young boy went missing, police organized the largest search in the history of their small town. First the boy's backpack was discovered five miles from home, and then his body was found 50 miles away. But the killer had been careless, and the evidence he left behind would lead police directly to him.

The decomposed body of a young woman was discovered in a Bakersfield irrigation canal. If there was trace evidence, it had been washed away. Another victim was found in that same canal a year later; this time, the perpetrator had been careless. The shoe prints found at the scene would lead police to the most unlikely of killers.

Police initially suspect that the death of a gay student is a hate crime, until just three strands of hair and some microscopic cells help them unravel a web of lies, and to find the real motive for the murder.

In 1994, 19-year-old college co-ed Shannon Melendi disappeared while at Emory University in Atlanta. For ten years, her disappearance of remained a mystery, until new scientific testing cast a different light on someone who had been a suspect from the beginning.

A millionaire and his family were executed in their own home. For three years, the murders went unsolved and then a 30-year-old box of ammunition and some fluorescent fibers revealed the ultimate betrayal.

When a young girl was found dead, police quickly arrested the most likely suspect. But cutting-edge technology from NASA enabled a forensic odontologist to prove the wrong man was behind bars. With the killer still on the loose, the investigation was far from over.