A new fingerprint identification system known as I-AFIS helps Texas detectives track down a killer after three years of searching. And a Georgia investigator gets to the bottom of a 16-year-old murder case.

A pawned gun and a stolen pick-up truck are the clues that investigators need to solve an elderly man's murder. And a tip from a prison informant cracks open the 15-year-old case of a man who had his ex-wife killed.

A police officer helps solve an 18-year-old murder case when he finds the prime suspect-his older brother. And a biker with a bloody finger is the clue that police need to put away a rapist who assaulted 31 women over six years.

After an Arkansas man confesses to the brutal murders of two women, police are shocked when the DNA evidence shows that he isn't the killer. And a DNA profile on a scarf helps solve the 21-year-old cold case of an Ohio woman.

Police in Overland Park, Kansas, hunt for over 15 years for a serial killer who lures women to Kansas for sadomasochistic sexual trysts at hotels. With unprecedented access to surveillance photos and video from the investigation, we go inside the probe.

A forensic dentist helps police nab a child killer by showing that the teeth marks on the killer's arms matches the teeth of the murdered boy. And telltale blood stains on a blue bandana solve the 10-year-old case of a teenage girl murdered.

When a Nevada couple demands the return of a baby they had sold to another couple, the burned body of the baby turns up in Arizona.

A California jury convicts Kevin Green of raping and bludgeoning his wife, despite his claims of innocence. But 15 years later, police nab a serial killer known as the "Bedroom Basher" and discover that Green may have been wrongly jailed after all.

A man suspected of the cold case murder of his wife and son hatches a new plot to kill his mother and father; and detectives solve the 20-year-old murder of a teenager by tricking her killer into licking an envelope, then extracting DNA from the saliva.

The conviction of a man found guilty of sexually assaulting and stabbing an Ohio woman to death is overturned because his Miranda rights were violated when he was arrested.

Police suspect a gay man murdered a woman because she became too friendly with his boyfriend. And a man goes on a monstrous crime spree, abducting five women over 15 years and forcing each to spend months and even years as his sex slave.

A Miami undercover operation nabs the man who beat four black prostitutes, doused their bodies with gasoline, and set them aflame. And DNA helps solve the cold case of a man who posed as a fisherman to get a 6-year-old girl's attention.

The killer of an 11-year-old girl is brought to justice when his ex-girl friend tells police he confessed the crime to her. And a mysterious set of bones puts police hot on the trail of a man who killed a teenaged boy 17 years before.

Forensic testing, unavailable at the time of the murder, helps police solve the 20-year-old murder of a California beauty queen; and two hairs pulled from a bandana used in a double murder is the evidence that police need to put the killer behind bars.

Four retired law enforcement officers, known as the Cold Case Cowboys, help track down the killer of a man wanted for rape and robbery.

Business cards found at a murder scene plus 38 years of advances in DNA technology reveal the killer of a 19-year-old New York woman. And, the lead suspect in a 22-year-old murder confesses after police take DNA samples from him.

Police suspect brothers J.R. and Coco Duvall beat two Michigan hunters to death, chopped up the bodies, and fed them to pigs; and a serial rapist, who holds a mini-flashlight in his mouth to blind victims, is nabbed.

A phone-sting operation produces a big surprise and helps police nab the killers of a San Diego man several years after the case went cold. And a California district attorney uses an unprecedented legal strategy--a "John Doe" warrant.

Police play a wild hunch that pays off in the capture of a serial rapist. And after 26 years, investigators finally solve the murder of a 6-year-old girl who had been forced to take a cold-water bath as punishment for painting her nails.

An eerie note left on a grave helps solve a 12-year-old case of murder, and an exhaustive questioning of a mother helps police unravel the mysterious deaths of three of her children.

A scheme to bribe a country music magazine to manipulate the charts leads to murder in Nashville and a 13-year hunt for the killer; and a murderer's plan to hide his gun and ammunition is foiled.

A dry cleaning tag inside a sweatshirt left at a crime scene helps police track down a serial killer and rapist who had been eluding them for years.

Police hunt for a man who killed three women in three different hotels, not far from one another in Des Moines, Iowa, over a 5-year period; and police get a killer to confess.

A kidnapper grabs 8-year-old Chad Choice from his home in Texas, then torments his parents with two ransom demands. The case goes cold until the parents receive a chilling package in the mail that contains a letter--and a skull.