John E. Douglas is a former special agent with the US Federal Bureau of Investigation, one of the first criminal profilers, and a criminal psychology author. His works include Mindhunter, Obsession, and Journey Into Darkness, among others.
Novelist and journalist Mark Olshaker was born in Washington, D.C., on February 28, 1951. He graduated from George Washington University in 1972. Olshaker was a special correspondent for the St. Louis Dispatch in the 1970s. Although best known for his collaborations with former FBI profiler and world-renowned criminal psychologist John Douglas (beginning with Mindhunter), he also written Virus Hunter: Thirty Years of Battling Hot Viruses Around the World, and The Edge. As a filmmaker, he was the writer and director of Discovering Hamlet (1990), a behind-the-scenes documentary of Kenneth Branagh's first theatrical encounter with the character he would eventually bring to the big screen.