After 17 years of writing about cold cases, US investigative journalist Billy Jensen decides to solve homicides. Two catalysts push him forward. The first is a random coward punch and subsequent death captured on CCTV. The second is the sudden death of his friend and fellow amateur sleuth Michelle Macnamara, author of I’ll Be Gone in the Dark. The assistance he provides to police results in fresh investigations and convictions making the book true to its title.