What is the main conflict in The Alienist by Caleb Carr?

The Alienist is the first foray into fiction by military and diplomatic historian Caleb Carr. This novel is set in 1896 at the advent of the psychological investigator. Dr. Kreizler is a psychologist who is often shunned by colleagues and polite society due to his unique views regarding the mentally ill. However, it is Kreizler Theodore Roosevelt, the police commissioner, turns to when a serial killer begins targeting New York's poor, immigrant children. With the help of his good friend, reporter John Schuyler Moore, a police secretary, and a pair of police detectives, Kreizler will use a psychological profile to track and catch the killer. The Alienist is a psychological thriller with a mix of true history that leaves the reader not only entertained, but fascinated by the rich detail drawn from reality.