Time and place: May 1951, mainly London, the last weeks before Guy Burgess and Donald Maclean fled to the Continent and thence to Moscow. But technically and thematically the film really reflects the era when it was made, thirty-odd years later. All the main characters in this story were dead and ready for reimagining, beyond the reach of libel actions. The 'Cambridge Spies' were a hot property in the 1980s and figured in a number of dramatizations, at least two of them by Alan Bennett.
Scriptwriter Robin Chapman frames the story in the conceit of a homosexual tearjerker. Blunt and Guy Burgess are depicted as longtime lovers. Lord knows they weren't. This theme is hammered in further with suggestions that Burgess had also had relationships with Donald Maclean and Goronwy Rees. I suppose he didn't find enough dramatic interest in the source material.
For additional soap-operatic filler, we get lots and lots of anxious, tearful domestic scenes between Mr and Mrs Rees. This comes as a surprise, since Rees was a decidedly minor character in the actual events. He's in the script for exposition purposes, to explain to his wife how one could become a communist at Cambridge, and then a Soviet spy as well. In real life, a drunken Donald Maclean had once denounced Rees at their club—"you used to be one of us, but you ratted." We don't see this encounter, but the Rees couple keep talking about it. The writer is trying to sketch in the motives of the unattractive, seldom-seen Maclean character. Here and elsewhere in the script, major plot points happen offscreen or by allusion.
The principal members of the cast all look about 15 years older than the characters they're playing. Burgess is written as a promiscuous gay blade, bubbling over with tales of adventure and conquests, but in Anthony Hopkins's depiction he's a dissolute old perv. He keeps being told how healthy and fit he looks, but here his looks are not deceiving. It all comes across as whimsy, like a D'Oyly Carte production where portly performers of fifty-five summers sing about being sprightly young youths and maidens. Ian Richardson as Blunt is more acceptable, because even if he's far older than the 45-ish Blunt of 1951, he does resemble the older Blunt whom most people knew from the papers and television in 1979. The fact that Ian Richardson had also played a commie spy in the original 1979 BBC2 'Tinker, Tailor, Soldier, Spy' gives him a comforting familiarity and authority.
The real Kim Philby was still sloshing about in Moscow in 1985, but he scarcely figures here except as a minor offscreen Mrs. Grundy. Guy Burgess's chorus-boy flatmate Jack Hewit was still around and in England in the 80s, and would be trotted out for interviews in the Spectator or whatever; but Jackie doesn't make it into this script. (In his place is a swishy clerkly type named Jimmy.)
To keep the script self-contained and the production low-budget (apart from the cast), the film is shot mainly in cramped interiors, occasionally relieved by picnicky scenes in the countryside. It all has the look and feel of a BBC series of the 1970s or 80s. Interior scenes are shot with some kind of low-light film, giving visuals of saturated color (blues and greens especially) though they are a bit soft and fuzzy to the modern HD-trained eye. Exteriors are sharper but washed-out by comparison. All scenes seem to be done with 16mm film, so you don't get the jarring contrast so common with certain BBC products of the era, where you pass back and forth between film and video. (The rare outside scenes in 'Upstairs, Downstairs' always seemed to take place in a different universe.)
It's not quite cinema verité, or even pop history, but it does accurately convey the sentiments and perspectives common a generation later. Until 1979, the story of Burgess, Maclean was mainly oft-repeated, tabloid stuff, with most important information still concealed from public view. After that, with blasé acceptance of homosexuality and the winding-down of the Cold War, the story of the Cambridge Spies became a never-flagging public obsession, with secrets yet to be uncovered.