Season 13 - Episode Guide

A bag full of evidence recovered from an iced-over river helps to reveal the murderer of a businesswoman in her own shop.

In 2006, Texas real estate agent Sarah Anne Walker was found murdered in a model home. Weeks later, a witness came forward who may have seen the killer. Police used forensic hypnosis to help him recall every detail of the man's appearance. His description was used to create a composite sketch, which investigators used to pull the killer out of hiding.

In 2003, Jason MacLennan returned home after a night out with friends and found his father's body lying in a pool of blood. There were shoe impressions outside in the snow. Police needed to determine who had the most to gain from his death.

After a politician dies of an apparent heart attack, an observant medical aide suspects poisoning and takes blood and urine samples. They become crucial evidence when investigators learn of incriminating remarks made by a suspect.

A U.S. Navy air traffic controller is found raped and murdered in her own home, and the body of one of her male co-workers is found right next to her bed. Is this crime the result of workplace sexual harassment and rape?

A man is found stabbed to death after a night in a strip club. A drop of blood on a bedspread becomes critical evidence five yeas later.

In 2000, the body of an exotic dancer was found beneath a New Jersey bridge, making police believe she committed suicide. But evidence at the scene proved not only that she'd been carried to the bridge and thrown over the side, but also that she was alive when she fell.

A construction foreman's murder is solved when an investigator notices some unusual characteristics of a few drops of blood.

In 2000, Judy Southern came home from work and was shot by a gunman waiting for her. Her husband Allen arrived afterwards, called 911 and drove her to the hospital. She died on arrival and the investigation focused on her husband Allen, but forensic analysis and a suicide note found at the scene pointed to someone else.

A woman's story seemed far fetched: A man wearing only underwear and gloves broke into the house, stabbed her boyfriend to death, and raped and terrorized her for hours afterward. But the evidence at the scene supported her story, and investigators turned for help to the FBI and their criminal profilers.

Suspected in the murder of his mother, a Delaware man tries to convince detectives that the real killer is a hitchhiker he had picked up.

A family vacation turns into a terrifying search for a missing wife and baby, then becomes a manhunt for a killer who committed a horrific crime.

A college student is abducted and murdered five days before Christmas. Eight years pass before a cell phone and a pair of running shoes implicates a suspect.

A North Carolina woman is raped and strangled in her apartment. Authorities are unable to link the prime suspect to the homicide, until they discover a connection to an unsolved Michigan murder that was committed a few years earlier.

A college student is reported missing, and police discover blood spatter in her boyfriend's bedroom – blood spatter someone has gone to great lengths to conceal.

A serial rapist is on the loose in a Texas town. No one knows where he'll strike next, but the audacity of his attacks and the escalation of violence against his victims make finding him imperative.

The victim has been stabbed more than thirty times, and the crime scene is awash with her blood. Near her head, police discover a distinctive button with strands of thread still attached. If they can find the owner of the shirt the button came from, they'll also find the killer.

A young woman attends evening church services... then disappears. When her abandoned car is found, the tank is empty and a gas can she kept in her trunk for emergencies is missing. Eyewitnesses place her at a nearby gas station, getting into a van, but their descriptions of the vehicle don't match. Three days later when her body is discovered, the search for the driver of that van intensifies.

When a nine-year-old girl goes missing, police and volunteers spend weeks searching for her. A psychic's vision leads to a field where her body is discovered, along with what investigators hope is enough evidence to also find her killer.

Digital enhancement of security camera video shows that what appears to be a casual encounter is actually a forced abduction, leading to murder. The perpetrator's MO is remarkably similar to another murder which occurred five months earlier, 15 miles away. When investigators learn the crimes might not be isolated or random, they also realize a serial killer may be on the loose.

The woman was sexually assaulted, stabbed, and left for dead. She survived and provided a description of her attacker. When someone who fit the description came forward, police were sure they had their man… until the DNA evidence proved them wrong.

The victim was a self-made man who never minced words. Perhaps he was murdered by a disgruntled employee. Perhaps the racy photos in his safe held the clue to solving the crime. Or perhaps investigators could follow the money and find the killer.

A family vacation becomes a nightmare when the wife is found face-down in the lake. Determining the manner of her death proves to be difficult… until a forensic pathologist uses a groundbreaking technique to discover the truth.

The woman in the back of the truck was flailing her arms, screaming. They thought she was doing something dangerous for the fun of it. But when they found a jacket near a pool of blood, they knew what they'd seen wasn't a joy ride; it was an abduction.

After he got inside, the assailant used an ax to kill the husband and critically injure his wife. Nothing was taken; this wasn't a robbery. DNA from skin cells collected hundreds of miles away would reveal the killer's identity and his motive for murder.

Two suspects living together were linked to a murder by bloodstained boots and a gun – items that belonged to the one who claimed he'd never met the victim. Police hoped the manufacturing code on beer bottles would prove who was telling the truth.

A serial bomber was on the loose in Illinois. Two churches had been bombed and one person was killed. Investigators had to stop the perpetrator before he struck again… and they hoped to find him by following a thin copper wire.

There was no apparent reason for the young, healthy college student to be dead. But when the medical examiner found the tiniest of clues during the autopsy, investigators were able to unravel the mystery of betrayal and revenge.

The victim had been stabbed more than a hundred times; her bedroom was blood-soaked. While her body was positioned in a suggestive way, she hadn't been sexually assaulted. Was this a sex crime, or the random act of a man with an intense hatred of women?

Even though the victim was burned beyond recognition, police were able to create a composite sketch from his remains and identify him. But knowing who he was isn't enough. Investigators still had to determine where he was killed and who wanted him dead.

Doctors don't know why the young scientist is gravely ill. When tests finally reveal the cause, it's too late to save him. Police hope that lab analysis of his hair, showing when attempts were made on his life and what was used, will lead to the killer.

A bullet-riddled car, a missing driver, and no witnesses. Was this an ambush or a random attack? Had the victim been abducted or was she dead? The answers lay in a unique clue, so tiny it was measured in millionths of a meter.

The teen's parents weren't really worried. She'd run away before, and they were sure she'd be back… but they were wrong. She was found on the side of the road, with her throat slit. Would a single hair lodged in a defensive wound lead to her killer?

Two women who lived in the same apartment complex were brutally murdered. The similarities of the crime scenes led police to believe they were dealing with a serial killer who hated women, and they had to find him before he struck again.

A college co-ed simply vanishes, and her fellow students are concerned about her safety… and their own. Weeks later, when a body is discovered 700 miles away in the ashes of a barn fire, an alert police officer realizes the two crimes might be connected.

The victim was well liked and successful, which made the brutality of the crime hard to understand. She'd written a name on the wall, presumably that of the killer, in her own blood. But to catch the killer, police would have to read between the lines.

The assistant manager of the restaurant had been stabbed to death. Police knew why he'd been killed: $8,000 was missing from the safe. As to who was responsible, his family and friends couldn't even imagine who'd want to hurt him.

The convenience store safe was empty and the clerk, missing. Hours later, her bound, half-naked body was discovered in nearby woods. Almost two decades would pass before advances in forensic science gave police the proof they needed to convict a killer.

When a man's body is discovered burned in a parking lot, police use tire track impressions and security camera video to track down the killer.

A respected surgeon was stabbed to death in the parking lot next to his office. The most likely suspect is seen having dinner in a restaurant at the time of the murder. But a cryptic conversation leads police to believe that, while the suspect may not have wielded the knife, he could very well have hired the man who did.

A young couple is found murdered in their Graham, Washington home; detectives discover shoe impressions, a partial palm print, and a neighbor's criminal past.

Terrified, the young girl hid in her bedroom while her mother was attacked and stabbed to death. The day was May 12, 1994, when Crystal Perry was viciously murdered in her home in Bridgton, Maine. Investigators had a wealth of evidence: shoe impressions, distinctive blood drops, and the killer's DNA. What they didn't have was a basis for comparison.

The gunman opened fire as the family of four entered their home, killing two and wounding the others. He'd pulled open a few drawers to make it look like a robbery, but the scene was clearly staged. When police pieced together the clues, they discovered an unlikely suspect and a carefully orchestrated plot. In short, on December 10, 2003, in a murder-for-hire scheme,

It was classic "overkill." The woman floating in the harbor of an upscale yacht club had been stabbed more than 50 times. Her ex-husband and daughter are missing, and investigators turn to forensic science to determine if they're searching for victims... or perpetrators.

On May 20, 2001, Carrie Nelson, then 20, was beaten to death while working alone in a state park office. There's a wealth of evidence at the scene, but it didn't implicate the prime suspect, it cleared him. The case went unsolved for six years until May 2007 when, in a routine check of DNA samples of prison inmates in South Dakota, police found a match with DNA samples gathered from the crime scene.

The evidence suggested the woman had been bound, sexually assaulted and murdered. Afterwards, the killer spent hours at the crime scene, wiping away his fingerprints and disposing of everything which might incriminate him, including the woman's body. Police now face a daunting task: they not only have to find the killer, they also have to find the body of the victim.

The couple spent Memorial Day weekend at the beach, and then they simply vanished. Their clothes and personal items were still in the rented condo, their car was parked outside, and there were no signs of forced entry or foul play. A week later, police would get an unexpected lead from a robbery in progress, and the evidence they found helped them to solve a crime of unparalleled violence and brutality.

Whoever stabbed the young mother to death had also savagely beaten her four-year-old daughter. Police had a suspect, but not enough evidence to tie him to the crimes. It would take 15 years and advances in DNA technology to bring the killer to justice.

The woman hadn't shown up for work in two days, and her boss reported her missing. When her body was found, the evidence pointed to suspects who claimed they had nothing to do with the crime. The victim, herself, would help police prove they were lying.

The investigation of an exotic dancer's disappearance leads to an isolated site where someone has been shot and cremated. Soft tissue attached to a piece of a foot yields enough DNA for a genetic profile, and positive identification of the victim.