Moore works with Seattle's Snohomish County Sheriff's Office and takes on her first-ever cold case as a genetic genealogist – the double homicide of Jay Cook and Tanya Van Cuylenborg. The young couple disappeared in 1987 after taking a ferry from Vancouver to Seattle and were later found miles apart, gagged, bound and brutally murdered. With a smattering of clues, but no real leads, the case was cold for 30 years. The episode includes interviews with Jay's parents, Gordon and Leona Cook; Tanya's brother, John Van Cuylenborg; Snohomish County law enforcement retired Sheriff Rick Bart and Detective Jim Scharf; and radio reporter Hanna Scott.

Investigative genetic genealogist CeCe Moore works with the New Madrid County Sheriff's Department on the 1998 murder of Sherri and Megan Scherer, a mother and daughter from New Madrid, Missouri. As the investigation takes Moore and detectives on a series of unexpected detours across the country, they uncover the identity of a previously unknown serial killer and Moore ends up meeting with the killer's daughter. The episode features interviews with Steven Scherer, son and brother to the victims; law enforcement from New Madrid and Greenville, South Carolina, and Memphis, Tennessee; the killer's daughter Deborah Brashers-Claunch; DNA expert Ruth Montgomery; and TV reporter Kathy Sweeney.

Police in Idaho Falls, Idaho, have spent the last 23 years trying to solve the case of 18-year-old Angie Dodge who was raped and murdered in her own apartment in 1996. They turn to investigative genetic genealogist CeCe Moore, but no genetic genealogist has ever solved a case using such degraded DNA. Despite the challenge, Moore is able to come up with the name of the potential killer. The episode follows the Idaho Police Department as they track the suspect, collect his DNA and match it to the DNA found at the crime scene. Cameras are rolling as police move in for a heart-pounding arrest. Moore's work on this case also helps exonerate Chris Tapp, who was wrongly accused of Dodge's murder and spent 20 years in prison.

The killer of 8-year-old April Tinsley taunted police for decades in Fort Wayne, Indiana, leaving notes and threats with viable DNA samples, but they still couldn’t catch him until now. Interviews featured in the episode include April’s mother, Janet Tinsley, and cousin Kristina Snyder; Fort Wayne Police Department’s Detective Brian Martin and retired detective Danny Jackson; coroner Chris Meihls; retired forensic scientist Linda McDonald; reporter Jamie Duffy; and Parabon NanoLabs’ founder Steve Armentrout and director of bioinformatics Ellen Greytak.

From 2006 to 2008, a series of unsolved rapes haunted residents in Fayetteville, North Carolina. Investigative genetic genealogist CeCe Moore works on the case with the Fayetteville Police Department while she attends CrimeCon, an annual true crime convention held in New Orleans. The episode includes interviews with survivor Kobi Haschen who bravely came forward with her story, Fayetteville Police Department’s Lieutenant John Somerindyke and former supervisor Lieutenant Kellie Berg, sexual assault nurse examiner Liz Herring and reporter Paul Woolverton.

CeCe Moore works her first active case, the rape of a 79-year-old woman.