Hank Castor has been a law enforcement officer most of his adult life. Devastated by the unsolved murder of his wife, he abandons his career as a federal agent to pursue the killer and exact revenge.History professor Eldon Quist's carefully organized world has come crashing down. Accusations of plagiarism, sexual misconduct, and foul play have stripped him of all he held dear.Charles Redhorse, a larger than life character we met in the first installment of Sound Investigations - A Deadly Dive, has embedded himself into the lives of Hank and Eldon and comes to them for help when his nephew is accused of murdering a neighbor. While Eldon and Hank embark on this investigation they become involved in a long unsolved case of missing teenagers with a mysterious connection to the local sheriff. Amidst all of this, Hank's violent past surfaces when bones are discovered that are linked to his actions from a prior visit to the area.Uncovering a body at a local construction site, seeing the FBI discover bones linked to an international terrorist group and unraveling a surprising case of a teenage love triangle gone bad, Hank and Eldon find their lives endangered as they pursue clues that touch both the past and the present.