| 角色 | 饰演者 | 角色介绍 |
| J. Edgar Hoover | 莱昂纳多·迪卡普里奥 | |
| Clyde Tolson | 艾米·汉莫 | |
| Helen Gandy | 娜奥米·沃茨 | |
| Anna Marie Hoover | 朱迪·丹奇 | |
| Robert Irwin | 乔什·汉弥尔顿 | |
| Mitchell Palmer | 杰弗瑞·佩尔森 | |
| Roberta Dixon Palmer | Cheryl Lawson | |
| Palmer's Daughter | Kaitlyn Dever | |
| Inspector | Brady Matthews | |
| Dwight Eisenhower | 冈纳·赖特 | |
| Franklin Roosevelt | David A. Cooper | |
| Agent Smith | 爱德·维斯特维克 | |
| Head Secretary | Kelly Lester | |
| Dickerson N. Hoover Sr. | Jack Donner | |
| Hoover as a Child | Dylan Burns | |
| Labor Dept. Lawyer | Jordan Bridges | |
| Caminetti | Jack Axelrod | |
| Emma Goldman | 杰西卡·赫特 | |
| Agent Stokes | Josh Stamberg | |
| Bureau Agent (1919) | Michael James Faradie | |
| Inspector Schell | 克里斯蒂安·克莱门松 | |
| Secret Service Officer | 比利·史密斯 | |
| Agent Jones | 迈克尔·拉代 | |
| Harlan Fiske Stone | Ken Howard | |
| Agent Williams | Scot Carlisle | |
| Raymond Caffrey | 吉欧夫·斯图兹 | |
| Edgar's Niece | Sadie Calvano | |
| Agent Appel | Allen Nabors | |
| Lawrence Richey | 瑞恩·麦克帕特林 | |
| Mr. Walters | William Bebow | |
| Robert Kennedy | 杰弗里·多诺万 | |
| Credit Director | Joseph Culliton | |
| Tailor | Scott Johnston | |
| Gangster | 汤姆·阿齐迪肯 | |
| Balding Agent | Mike Vaughn | |
| Agent Garrison | 麦尔斯·费舍 | |
| NJ Officer | Stephen F. Schmidt |
