The book follows the exploits of an octogenarian, Agustín Lara Camelia, a retired law enforcement executive living as a widowed recluse in the Pennsylvania countryside. An ill-advised response to an "escort" ad, ends tragically, and he finds himself facing a prison term for manslaughter. Because of his unique international background he is recruited as an unofficial infiltrator within Mexico by Agents of the US Department of Homeland Security Investigations who are investigating a sex trade organization with connection with a Mexican cartel controlling human trafficking between northern Mexico and the US. The old man finds himself conflicted while trying to atone for his crime and also follow the strict rules of HSI. Camelia relies on his experiences as a rookie police officer on the streets of Salinas, California. It was there that he last felt self-assured and learned that humanitarianism is the cornerstone of law enforcement, the part that gives purpose throughout a policeman's life.