Season 1

Kendall Francois is a john who frequents the Poughkeepsie, NY streets where he lives. For over two years, he picks up and murders eight prostitutes and is only discovered when the would-be ninth victim escapes and reports him to police. Over a two year period, eight women disappear from Poughkeepsie, NY. All of the women are prostitutes who work in the area. Several suspects come to light, but no evidence can ever be connected to them. Then in September 1998, a prostitute tells police that Kendall Francois tried to kill her. He had been questioned previously but said nothing incriminating and even passed a lie-detector test. When he finally confesses, a search of his home reveals eight bodies.

When Arletha Hopkins learns that her husband is abusing her daughter she kicks him out. He exacts revenge by killing her and forcing the girl to help hide the body. No one finds out till years later when she becomes pregnant and the story spills out. Anthony Hopkins is a traveling preacher in Mobile, Alabama. Left with eight children to raise after his wife purportedly leaves him, he tells his congregation that she died giving birth. But it's not as it seems — Hopkins was forcing his stepdaughter to engage in sexual acts. When his wife finds out, he kills her and forces his stepdaughter to help him conceal the body. No one finds out until years later, when the girl becomes pregnant with his child and the harrowing story spills out.

Profiling serial killer and rapist David Alan Gore and his accomplice, his cousin Fred Waterfield.

The heinous crimes of Gerald and Charlene Gallego, a married pair of serial killers, are detailed.

Career criminal Gary Evans is suspected to be behind the disappearance of one of his former associates. After an intense manhunt, Evans is apprehended in Vermont and confesses to a life filled with crime and killing, with five murders to his credit. Gary Evans makes his living robbing antique stores throughout New York State and is well known by police in the area. After two years of having no contact with him, police are thrust back onto his path in late 1997 — a path that is littered with bodies of his former associates and a few store owners who didn't get out of the way fast enough. Evans is eventually captured and confesses to the murders before killing himself, having never been prosecuted.

Elizabeth Gatenby's mother is in the process of divorcing unsuspecting husband, Bruce Firman. In an elaborate plan to ensure her mother gets everything, Elizabeth hires her son and another young man to murder Bruce. Bruce Firman is found dead in his garage by soon to be ex-wife, Margaret Benesch, and her daughter, Elizabeth Gatenby. Suspicion immediately falls on Benesch — as the sole heir in Firman's will, she is entitled to receive everything, but produces a rock-solid alibi. When investigators dust Gatenby's rental car for fingerprints, one match those of a 17-year-old teenager. He said he'd been hired to kill Firman by Gatenby's son, Byron, who confesses that his mother planned it all.

In 1980, Jamie Kellum kills college friend, Katherine Foster, in a fit of jealous rage. Two decades later, Kellum, now Jamie Letson, tells her AA sponsor of her crimes, leading police to make an arrest in a 20 year old case. The body of Katherine Foster is discovered at the University of Alabama. A student reports hearing gunshots the night before she was found, leading police to conclude that Foster was shot and left in the woods. Suspicion falls on a campus security guard, an apparent suicide who was obsessed with Foster's murder. The guard is cleared and the case goes cold for two decades before a whispered confession to an AA sponsor leads police to arrest and convict Jamie Letson, a friend of Katherine's.

Erin Chorney is missing for over a year. Police suspect her boyfriend but have no evidence. In an elaborate sting operation, police officers convince Chorney's killer to tell them how he strangled her to death. 18 year old Erin Chorney goes missing. Investigators immediately suspect her abusive boyfriend, Michael Bridges, but do not have enough evidence to arrest him. Over a year later, they turn to police for help. Officers go undercover as figures in charge of a powerful criminal organization. They tell Bridges that if he comes clean about his past, they will be able to trust him to join their association. When Bridges confesses to murdering Chorney, police move in and finally get their man.

The 1986 murder of Helle Crafts is discussed.

Stacey Castor poisons her first husband with antifreeze and gets away with it. She is only caught after killing her second husband the same way and attempting to murder her daughter and frame her for both deaths. Investigators find David Castor dead with a glass of bright green liquid nearby. His wife Stacey's fingerprints are on the glass and police locate a turkey baster in the garbage with David's DNA on the tip. They suspect Castor poisoned her husband. As evidence against her mounts, her daughter Ashley is found unconscious with a note proclaiming she killed David. Upon Ashley's recovery, Stacey is found to have poisoned both of them — and her first husband too.

Police find five bodies of young women, all strangled with a particular slipknot. Eventually they tie Paul Durousseau to the murders through DNA samples, fibre analysis, and phone records from the cab he drove. Nikia Shanell Kilpatrick, 19, is found bound and strangled with a cord in her Jacksonville, Florida apartment. Within a month, three more bodies are discovered and attributed to the same killer, each found strangled with a cord fashioned into a peculiar slipknot. Police begin to find links - including DNA samples, fiber analysis, and cab and cell phone records — connecting taxi driver Paul Durousseau to the murders. He is eventually convicted of five counts of first-degree murder.

Greg Markwardt kills his sister-in-law, Kathy Odom, in 1987. He remains free for nearly two decades, but new DNA techniques allow a lamp cord from the scene to be tested, proving his DNA to be a match and forcing his arrest and subsequent conviction. In 1987, Kathy Odom is found stabbed to death in her home. There are several signs suggesting that she knew her attacker, but detectives cannot make an arrest. Years later, a new technique is developed that allows DNA to be collected from items used in a murder. The lamp cord that was tied to Odom's wrist is subsequently tested for DNA. Her brother-in-law, Greg Markwardt, turns out to be a match for the profile and after fifteen years, is arrested for the murder of Kathy Odom.

The crimes of serial killer Dean Corll are detailed.

The crimes of Cary Stayner, who killed four women near Yosemite National Park, are recounted.

Police find a stolen, blood-stained SUV across from missing Susan McFarland's home. Evidence links both a suspicious man and her husband, Richard, to it. When police finally find Susan's body, they tie it to Richard via a left-behind candy wrapper.

A 1979 double-murder case unfolds.

The crimes of a serial killer called the Night Stalker are detailed.

Police find the body of a missing 10-year-old girl in a stream; DNA evidence is used to find the killer.

Police turn their attention to a husband after he reports his wife missing.

A beauty queen's body is found in a field near Sydney Australia; the accounts of eyewitnesses point to a local gang leader.

The wife of a pastor is found murdered in her bed; a text message shows that the pastor was having an affair with his nanny.

In Ohio, Claude Hawkins is shot to death while fishing; his murder is similar to deaths in nearby counties.

Suspicion surrounds the death of a patient of respected neurologist Richard Boggs, but an autopsy finds that the man died of natural causes. A million-dollar payout on the man's life insurance helps authorities get to the bottom of the twisted case.

A man shoots immigrants on the streets of Stockholm, Sweden, using a laser-guided rifle.

A couple is found guilty of the rape and murder of Taunja Bennett until a letter signed with a happy face confessing to the crime is sent to a Portland newspaper.

Several women from Kansas City go missing after going to Missouri to meet a man they met online.

Atheist Madalyn Murray O'Hair vanished in 1995 with her family leaving a sinister note claiming a family emergency.

A house fire breaks out at the Blaine residence in Vinton, VA. When the entire family is found dead inside, it is quickly realized that the fire is not what killed them. What starts as a possible murder suicide soon turns into something far worse.