Further novels featuring this character are:
As the protagonist is anonymous in all of these novels, it is open to debate whether or not Harry Palmer is the narrator of the last two novels. Deighton said that the narrator of Spy Story is not the same character as the narrator of The IPCRESS File; for most of Spy Story, the narrator is named and addressed as 'Patrick Armstrong' — although, as another character says, "We have so many different names". Additionally, he is reported to be in his late 30s whereas the narrator of The IPCRESS File (1962) was born in 1922 or 1923, thus suggesting they are different characters.
Despite this, all these novels have been unofficially titled the Harry Palmer novels, based on the protagonist's name in the film adaptations of The IPCRESS File, Funeral in Berlin, and Billion Dollar Brain.
Encouraging the unitary concept — that each novel features Harry Palmer — is the 1974 dust jacket to the Harcourt, Brace & Jovanovich American edition of Spy Story, the blurb is: "He is back, after five long-years' absence, the insubordinate, decent, bespectacled English spy who fought, fumbled, and survived his outrageous way through the best-selling Horse Under Water, Funeral in Berlin, and the rest of those marvellous, celebrated Len Deighton spy thrillers". Likewise, on the 1976 edition dust jacket to Catch a Falling Spy, the novel features "Deighton's familiar hero, our bespectacled Englishman". Moreover, some characters from Yesterday's Spy (1975) earlier appeared in Spy Story (1974), although "Harry Palmer" is not amongst them.
It is theorised that the protagonist in another of Deighton's spy novels, An Expensive Place to Die (1967), also in the first-person-anonymous narrative, is "Harry Palmer", however, differences in characterisation and plotting indicate someone else other than Palmer.
The IPCRESS File was published in November of 1962, soon after the release of Dr. No (the first James Bond film). Unlike Ian Fleming's spy, Len Deighton's spy is working class, hindered by bureaucracy, wears eye glasses, shops in supermarkets, lives in a back street flat and seedy hotels, and craves a pay rise.
When The IPCRESS File sold well, EON producers Harry Saltzman and Albert Broccoli approached Deighton to write the script for the next 007 film, From Russia With Love (1963), however, despite Deighton's efforts, little of his screenplay was filmed. Saltzman, instead, decided to use The IPCRESS File, and its sequels, as the beginning of a new secret agent movie series. The IPCRESS File was designed to have a style different from the James Bond movies, although Saltzman employed many Bond movie staff, including production designer Ken Adam, editor Peter Hunt, and composer John Barry; eventually, Michael Caine was chosen to play the lead.
Needing to name the previously-anonymous secret agent, the production team chose "Harry Palmer", because they wanted a dull, unglamorous name to distance him from James Bond — the prevalent stereotype: a flamboyant, swashbuckling secret agent. In his memoirs, Michael Caine says producer Harry Saltzman thought up the surname "Palmer", and Caine innocently remarked that "Harry" was a dull name, realising his gaffe on seeing Saltzman's stare. Another origin story is that in a Len Feldman interview, Caine recalled "I made a rather bad social blunder, because, he said, 'What's the dullest name you can think of ?', and I said, 'Harry', and he said, 'Thanks very much.' And then he said, 'What's a dull surname ?', and the most boring boy in our school was called: 'Palmer', 'Tommy Palmer'. So, he said, 'All right, we'll call him Harry Palmer.'"
In the film version, Harry Palmer is a lowly army sergeant forcibly drafted to secret work, first for Army Intelligence, then the Foreign Office, to work away a prison sentence for black marketing. Harry Palmer has much in common with Len Deighton, including passions for cooking and classical music.
In the mid-1990s, there appeared two Harry Palmer films with original screenplays and starring Michael Caine:
Despite sometimes being titled Len Deighton's Bullet to Beijing and Len Deighton's Midnight in St Petersburg, Len Deighton did not participate in these films. Evidence of Michael Caine's popular identification as Harry Palmer is in Blue Ice (1992), wherein the hero is an ex-spy named 'Harry', who is much like Harry Palmer. In Austin Powers in Goldmember (2002), Caine's portrayal of Nigel Powers, father of secret agent Austin Powers, spoofs Harry Palmer.