The Criminal Psychology Research Team is affiliated with the FBI. They operate across states and mainly target serial murders. They build character profiles based on the suspect's criminal psychology and behavioral patterns, and determine the criminal's gender, age, occupational characteristics, living environment and even growth experience, so as to predict the criminal's next behavior until the criminal is arrested. Their members include: Dr. Spicer Reid (Matthew Gray Gubler), a young genius with high IQ and strong memory, who is responsible for data and information analysis; Aaron Hatch (Thomas Gibson), a tough guy with a cold exterior but a warm heart, who has strong communication skills; Puerto Rican boy Derek Morgan (Shemar Moore), an expert in compulsory criminal behavior; Penelope Guthia (Kirsten Vangsness), a chubby girl with ostentatious looks, who is a database expert; JJ (A.J. Cook), a beautiful media liaison, etc. Under the leadership of veteran agent David Rossi (Joe Mantegna), they flew to various parts of the United States to launch a series of murder-hunting operations.