Rust Cohle is a fictional character from the television series True Detective, created by Nic Pizzolatto. He is portrayed by actor Matthew McConaughey and serves as one of the main detectives investigating a series of ritualistic murders in Louisiana. Cohle is known for his philosophical outlook, troubled past, and unconventional investigative methods. Cohle's character is marked by his deep introspection and often bleak worldview. He struggles with personal demons, including the loss of his daughter and his experiences as an undercover narcotics officer. Throughout the series, Cohle's complex personality and unique perspective on life and crime are central to the narrative.