Mark Olshaker is an American author and filmmaker known for his work in the true crime genre. He has collaborated with former FBI agent John Douglas on several books, including "Mindhunter," which explores criminal psychology and profiling. Olshaker's writing often delves into the minds of serial killers and the methods used by law enforcement to catch them. In addition to his books, Olshaker has produced documentaries and television programs that focus on crime and justice. His work has contributed to a greater public understanding of criminal behavior and the complexities of the criminal justice system.