<P>--"Note" at the beginning of the novel </P> <P> At Roosevelt's request, Moore, Kreizler, and he meet the following morning in Roosevelt's office to discuss the case . Kreizler has examined the body and disagrees with the official coroner's report . He connects the Santorelli killing to that of a second case he knows of in which two children, Benjamin and Sofia Zweig, were killed and had their eyes gouged out . Roosevelt announces that he knows of two more murders that match the pattern . Roosevelt decides to investigate, but because Kreizler has such a dubious reputation as an alienist, and because the investigation will become politically difficult, he establishes a base of operations for them outside the police precinct . Politically, Roosevelt cannot afford to be associated with the investigation and is not involved with the day - to - day operations . </P> <P> Kreizler asks for some young detectives who are open to new methods and receives the help of Sara Howard, the first woman to be hired by the police department, and Marcus and Lucius Isaacson, two Jewish brothers who were hired when Roosevelt began removing corrupt police officers from the force . The Isaacsons bring sophisticated methods, such as the Bertillon system and fingerprinting, to the investigation, although these were not popular in New York City police departments at the time nor accepted in courts of law . </P> <P> The group begins to investigate the victims, hoping to understand the mind of the murderer by understanding his victims . They interview Georgio Santorelli's mother and discover, for example, that there was discord in his family . Georgio's parents had learned of his being manipulated into performing sexual acts for older boys in school, and the father's response was to try to beat it out of the boy . Georgio eventually left home and lived on the streets as a male - for - male prostitute . They also read the emerging science of psychology, such as the works of William James . Another body is discovered, and the evidence suggests that the victim knew his attacker . The team also deduces that the killer's agility on rooftops suggests that he is familiar with mountain - or rock - climbing . </P>

Who is the killer in the alienist based on