Based on the same real life events as Another Country (1984), Cambridge Spies (2003), History in Faces: Cambridge Five (2011), Philby, Burgess and Maclean (1977), An Englishman Abroad (1983), Tinker Tailor Soldier Spy (2011), Tinker Tailor Soldier Spy (1979), Blunt (1987), Traitor (1971), Blade on the Feather (1980), The Jigsaw Man (1983) and influenced the source novels of The Fourth Protocol (1987), The Innocent (1993) and others works such as A Different Loyalty (2004) and Olding (2019), even in minor form like in The Imitation Game (2014).
Alan Bennett's other film about the Cambridge spies, An Englishman Abroad (1983), is about how actor Coral Browne met Guy Burgess in Moscow during the Shakespeare Memorial Theatre's tour of Leningrad and Moscow in 1958-9. Edward de Souza, who here plays Collins, was a member of the company and was on that tour.