"The Alienist" is a historical crime novel written by Caleb Carr, published in 1994. Set in 1896 New York City, it follows a team of investigators, including Dr. Laszlo Kreizler, a psychologist, as they try to solve a series of gruesome murders of young boys. The story delves into the early understanding of criminal psychology and the methods used to profile criminals. The novel combines elements of mystery and psychological thriller, offering insights into the social issues of the time, such as mental illness and policing. It also features real historical figures, including Theodore Roosevelt, who plays a significant role in the investigation.