The 34th entry in Patterson's long-running Alex Cross series functions as a prequel/companion piece to the 1993 original, Along Came a Spider, revisiting Cross's rookie year as a D.C. homicide detective — decades before he became the veteran profiler readers know. In the present day, police discover a hidden cabin containing a journal titled "Profiles in Homicidal Genius," written by Cross's most notorious nemesis, Gary Soneji, before Soneji's presumed death. The journal reveals that Soneji and Cross's history began earlier than Cross ever realized, and that mistakes Cross made as a young detective may have had consequences he's never fully reckoned with. The narrative alternates between the present-day investigation, as Cross studies the journal for new leads, and flashback chapters set twenty years earlier, when young Detective Cross — partnered with lifelong friend John Sampson — worked his first major homicide cases, including a killing modeled on the "Son of Sam" pattern and one styled after the Boston Strangler, while simultaneously navigating a gang war and his relationship with his first wife, Maria (whose eventual death shapes the entire original series). The novel functions as both a serial-killer thriller and a character study, deepening Cross's origin and adding retrospective weight to events referenced only briefly in earlier books. Reviewers have generally responded well to the prequel structure, noting it "humanizes" Cross and gives long-time readers new context for his defining rivalry, even as some found prequels an inherently limited device.