The footage of the entrance gate of C.I.A. Headquarters in 1975 was re-used from the film Spy Game (2001), which Tony Scott, of Scott Free Productions, directed. Perhaps as further interest, that footage is not of the C.I.A., but an abandoned telephone company entrance gate.
This marks the second time that Tom Hollander has played one of the infamous "Cambridge Five" spies. He played Guy Burgess in the BBC miniseries, Cambridge Spies (2003).
Cockroach Alley is the cluster of wooden "temporary" buildings on the Mall in Washington (National Mall) that housed CIA's first offices in the late 1940s. Buildings I, J, K, and L shuddered in the slightest breeze, and they smelled; officers walked cautiously over the rotting floors.
Michael Keaton, Chris O'Donnell, and Alfred Molina have been in comic book movies. Keaton played Bruce Wayne (Batman) in Batman (1989) and Batman Returns (1992), O'Donnell played Dick Grayson (Robin) in Batman Forever (1995) and Batman & Robin (1997), and Molina played Otto Octavius (Doctor Octopus) in Spider-Man 2 (2004).