McNamara meets for coffee with Fred Ray, a detective who investigated one of the GSK’s Santa Barbara murders. McNamara questions Ray about his experience interrogating young teenage boys arrested for prowling homes. Ray notes that many of the boys were motivated by a curiosity about the interior of other people’s private spaces. Ray’s empathetic demeanor made the prowlers feel at ease and able to open up. McNamara questions Ray as to whether he believes one of the prowlers he interviewed could have been the GSK. Ray says he doesn’t believe he interacted with the GSK, telling McNamara that he would “know” if he met the killer (258). 

McNamara describes several suspects in the decades-long GSK investigation. Jim Walther is one such suspect, intercepted by police in Danville, California in February 1979. The police initially suspected Walther because his physical profile matched that of the GSK’s. However, Walther is eliminated as a suspect when a saliva test reveals him to be a secretor, not a non-secretor (a person whose bodily fluids do not contain traces of blood). Decades later, Holes seeks to re-open the investigation into Walther, as he believes that “suspect eliminations based on secretor status were unreliable” (263). Holes is unable to locate Walther, who has effectively disappeared.