Laszlo Kreizler is a fictional character created by author Caleb Carr in the historical thriller novel "The Alienist." He is a brilliant psychologist and investigator in late 19th-century New York City, known for his innovative methods in criminal profiling. Kreizler is often portrayed as a complex and introspective individual, deeply committed to understanding the human mind. In the story, Kreizler leads a team to solve a series of gruesome murders, utilizing his expertise in psychology and forensic science. His character reflects the emerging fields of psychology and criminology during that era, making him a significant figure in the narrative.