Jim Wormold became agent 59200/5, acting from Cuba, and mislead everyone in the USA intelligence community. Anticipating the cynical style of "John Le Carré", Graham Greene wrote the plot in 1958. And I wrote about him, and his connections with Portugal, 10 years ago [see here].
Greene was in charge of the Portuguese desk in Section V of Mi6 during WW2. Harold Russell («Kim») Philby was a close and dangerous connection. Greene wrote the preface of Philby's memoirs My Silent War, after the escape of the late to the USSR.
Much later he traveled trough the country with his friend the Catholic priest Father Durán and was hosted by Olga Nicolis de Robilant (Cadaval) at his villa in Sintra.
Tonight, wandering in the internet I found the trailer of the film.