Edgar Hoover, director of the Federal Bureau of investigation (Leonardo DiCaprio Leonardo DiCaprio), who is in his 70s, dictates his memoirs at the invitation of Crime Chronicle. Hoover told the memoir's ghostwriter about his important life since 1919: the arrest of leftist leaders, the arrest of notorious gang leaders, the detection of the Lindbergh kidnapping that shocked the United States, and so on. According to Hoover, he rejected public opinion, reorganized the Federal Bureau of investigation, introduced high-tech investigative techniques, and worked wholeheartedly for the peace and stability of American society. On the other hand, his private life has become a part of what he is trying to hide. When Hoover looked back on his life, there were still many turbulent factors in American society. Hoover's longtime personal assistant Clyde Tolson (Amy Hammer Armie Hammer) also seems to have an unusual relationship with him.