A young woman from out of town meets up with friends, and never returns to the hotel where she is staying with her family. Fearing the worst, they launch an investigation into her disappearance. Police are able to track down when and where her social media accounts were last used but the clock is ticking, and the longer it takes, the less hope the family has of finding their daughter alive.

The son of a millionaire inventor discovers his father's body on the kitchen floor, shot six times. Police have no shortage of plausible suspects, but each one has an airtight alibi. After 15 years, old fashioned 'gumshoe' detective work breaks the case open.

A man is found murdered in the bus shelter he was sleeping in. As the leads start to run dry, two more men are found murdered by escalating methods. A pattern emerges, a murderer is targeting the most vulnerable. But can the police rush to find their suspect before another life is lost?

Police know who committed the crime, but meticulous planning allows a mass murderer to escape detection for 18 years. Despite a change in name, location and a new family, a chance sighting on a TV crime show helps police pick up his trail again.

On his first night in town a man is brutally stabbed to death and his body dumped along a dirt road. Some acquaintances he had met earlier that day turn in his blood-stained car to police believing it to be the scene of the crime. With no witnesses the DA refuses to try the case. Years later, detectives re-examine the case, testing decade's old evidence with modern DNA technology.

A composite sketch and DNA are the only clues in the ruthless murder of a promising young intern. But forty years later, police lay a trap, and an unsuspecting predator finds that he has gone from hunter to quarry.

A couple finds a young woman near death in a rural Washington forest. After she succumbs to her injuries police identify the victim and struggle to find the culprit, eager to bring answers to a grieving family. It would take 48 years before clever police work and cutting-edge law enforcement technology find the killer.

A young woman is reported missing and then found days later in the elevator of a Seattle parking garage. A lack of evidence stalls the case for close to 50 years with only one suspect that turns out to be innocent. However, present-day advances in DNA tracing techniques bring forth a new suspect and authorities are closer than ever to finding out who the killer is.

In a Vancouver rooming house two people are found brutally murdered in a bizarre crime scene. Investigators search for answers, but it will be over 30 years before the investigation turns into a massive undercover sting operation designed to catch a killer. Will it work, and even if it does, will it be too late to get a conviction and bring justice to the victims?

A worker in Vancouver's Stanley Park discovers a shallow grave with two small skeletons. The infamous case would remain unsolved for seven decades, until DNA analysis provides a startling revelation and genetic genealogy finally tracks down the names of the child victims.

A young woman's body is discovered murdered in her own home in what appears to be a burglary gone wrong. As one by one suspects are eliminated, police fear that they have let the killer slip through their fingers for good, until a new invention decades later points the finger directly at the murderer.

A roadside discovery in Utah reveals a murdered woman wrapped up in sleeping bags and blankets. Efforts to identify her and the killer prove almost impossible. For more than 20 years the identity of the woman, and killer, remain a mystery, until new DNA collecting techniques brings authorities closer than ever to finding the identity of the victim and her killer.

An elderly woman is killed with such ferocity police dig deep to find her enemies. With a serial killer on the loose who preys on seniors even the most seemingly insignificant, will play a part in this game of life and death.

A young girl vanishes from her rural Canadian home and the search makes national headlines, along with the discovery of her body a few months later. Police link evidence to the wrong man, who goes through a decade of trials and suspicion. It will take three decades of advances in forensic science to find the killer.

A man is found dead in his apartment but the investigation quickly fizzles out. As more and more gay men are murdered around Toronto in the subsequent decades, his case is reopened. Finding the killer goes from not just being about one man to being about the safety of the entire gay community.

In Chicago in three boys go missing while on a trip downtown to see a movie. Two days later their bodies are found in a ditch. The entire city is shocked and horrified, and demands justice for the three innocent children, but it will be almost 40 years before answers start to come to light.

A woman is discovered brutally murdered in her hotel room just as she is about to start a new chapter in her professional career. It will take several stages of technological advancement until forty years later the identity of her killer is finally revealed with the aid of genetic genealogy.

An informant looking for a way out of jail tells police about a murder they never knew existed. Police enlist the help of a local newspaper to set up an elaborate sting operation not only hoping to catch the killers but to find out who the deceased really is.

On a stretch of highway near a small town in Minnesota, a woman's body is found in a ditch. Police are unable to identify the victim and she is buried as a Jane Doe. Decades later, after DNA technology becomes common practice in police investigations, a local resident makes it her personal mission to discover the victim's identity.

When a newborn baby is found deceased in a ditch, a community rallies to give him a proper funeral. The burial preserves DNA which, forty years later, will corner a woman who thought she'd discarded a secret no one could trace.

When newlyweds are discovered murdered in their home police are at loss as to who did it. After hundreds of interviews, even reaching out to psychics turns up no clues. With nothing to go on, the case goes cold for over 40 years until technology can catch up with the killer. It will take next generation genetic genealogy to uncover the truth.

The investigation into the double murder of teens in a lover's lane reveals dozens of suspects, but not one can be linked to the scene. Over sixty years later, new technology and the one single piece of perfectly preserved evidence reveal a shocking secret that almost remained hidden forever.

The body of a motel employee working the night shift is discovered tied up and badly beaten. As police investigate, they find the employee's granddaughter is also a victim. The investigation spans decades and crosses state lines as detectives follow false leads, dead ends, and even employ new criminal profiling techniques developed by the FBI, which leads them to investigate a notorious serial killer.

A young nurse is murdered on her way to work. After offering a reward for any information, the police quickly find and arrest their suspect. But as the decades go on, the investigation is called into question, and the real killer could still be free.

A 40-year-old Alberta resident vanishes without a trace until her charred body is found in an abandoned shack. The RCMP hit the case hard but without any strong evidence, the case quickly goes cold, leaving a vicious killer on the loose. Almost ten years later, the RCMP have to get creative if they want the murderer behind bars.

The body of a brutally murdered young Indigenous woman is discovered in a remote area of northern Manitoba. RCMP turn the town upside down and four suspect's names keep coming up. But with too little evidence and no one willing to talk, it takes over a decade before a tenacious new officer on the case finds a way to break the silence.