In Little Falls, Minnesota, a retiree's peace is shattered by a home break-in, culminating in a gruesome double-homicide. Investigators discover audio recordings of the killings, revealing what really happened and the killer's true motives.

A couple's fight reaches a tragic end when one of them is shot. A tape recorder that's captured final words becomes evidence in a trial, and when more tapes are found, the jury must examine a violent history and decide the fate of a possible murderer.

A mom accused of the murder of a stranger must clear her name by secretly-recording a confession from the man she claims is framing her. Sordid revelations of a secret life lead police to prove the guilt of an obsessive, cold-blooded killer.

A mother is gunned down next to her toddler, sparking a homicide investigation involving passion, kidnapping and intimidation. When cops discover a dictatphone, it leads them on the trail of intimate audio recordings that could prove reveal her killer.

In 1983, the Secret Service are on the trail of a counterfeiter. In a storage unit, they find sickening audio recordings of him torturing dozens of women. Analyzing the tapes, they realize that he may be one of the most depraved serial killers in history.

A mom of three in Georgia is killed after vanishing from home. Clues in the form of audio files captured by her tech-obsessed husband may be key to solving the mystery. As cops scrutinize the sounds, they make a grim discovery that betrays her killer.