| Name | Character | Episodes |
|---|---|---|
| Molly Parker | Alice Olson | 6 |
| Peter Sarsgaard | Frank Olson | 6 |
| Christian Camargo | Dr. Robert Lashbrook | 6 |
| Tim Blake Nelson | Sidney Gottlieb | 6 |
| Scott Shepherd | Vin Ruwet | 6 |
| Bob Balaban | Dr. Harold A. Abramson | 3 |
| Jimmi Simpson | CIA Agent | 2 |
| Dick Cheney | Self (archive footage) | 2 |
| Robert Mitchum | Jeff Bailey (archive footage) | 1 |
| Seymour Hersh | Self (archive footage) | 1 |
| Seymour Hersh | Self - Investigative Journalist | 1 |
| Jack Doke | Young Eric Olson | 1 |