| Name | Character | Episodes |
|---|---|---|
| Michael Keaton | James Jesus Angleton | 3 |
| Alfred Molina | Harvey Torriti | 3 |
| Chris O'Donnell | Jack McAuliffe | 3 |
| Tom Hollander | Adrian Philby | 3 |
| Stephen Bogaert | Elliott Ebbitt III | 3 |
| Angelo Tucci | CIA operative | 3 |
| Rory Cochrane | Yevgeny Tsipin | 3 |
| Ted Atherton | Frank Wisner | 3 |
| James Arnold Taylor | CIA Surveillence officer | 3 |
| Simon Callow | MI6 liaison officer Elihu | 3 |
| Kristin Booth | Adelle Sweet Kritsky | 3 |
| Anna Silk | Stella Bledsoe | 3 |
| Lynne Deragon | Female Cutout | 3 |
| Billy Parrott | CIA tech | 3 |
| Rick Roberts | William Colby | 3 |
| Dan Petronijevic | Young CIA Officer | 3 |
| Fernanda Dorogi | Agrippina | 3 |
| Craig Eldridge | Coach Waltz | 3 |
| Catherine McNally | CIA doctor | 3 |
| Phillip MacKenzie | CIA doctor | 3 |
| Richard Rifkin | Dr. Sydney | 3 |
| Natascha McElhone | Elizabeth Nemeth | 2 |
| Alessandro Nivola | Leo Kritzky | 2 |
| Ulrich Thomsen | Starik Zhilov | 2 |
| Alexandra Maria Lara | Lili | 2 |
| Cedric Smith | Allen Dulles | 2 |
| Alfred Molina | Harvey Torriti / The Sorcerer | 1 |
| Levente Törköly | Constantine Vishnevsky | 1 |
| Raoul Bova | Roberto Escalona | 1 |
| Alessandro Nivola | Leo Kritzky / Captain Duval | 1 |
| Mišel Matičević | Arpad Zelk | 1 |
| JB Blanc | Manuel Piniero | 1 |
| Antony Sher | Ezra ben Ezra, the Rabbi | 1 |
| Barry Flatman | Philip Sweet | 1 |
| Ramón Franco | Arturo Padron | 1 |
| Erika Marozsán | Azalia Ivanova | 1 |
| Martin Doyle | Dick Bissell | 1 |
| Hristo Mitzkov | Vanka Borisov | 1 |
| Joe Lisi | Sam Giancana | 1 |