"Left, right, left, we all fall down, Like toy soldiers" - Tinker Tailor Soldier Spy

In 1979, the BBC broadcast a landmark adaptation of John Le Carrié's 1974 novel, which remains one of the broadcaster's most beloved and acclaimed dramas.

Alec Guinness as George Smiley.

Bleak, desolate landscapes are present throughout the BBC's adaption of John le Carrié's novel Tinker Tailor Solider Spy. It's fitting that these are haunts for the bleak, desolate people who inhabit them - just one example of how this landmark series uses place to reflect character. In itself, there's nothing that remarkable about it, as it's the sort of thing that stories the world over have been doing for centuries. However, it being done in a BBC drama series during a period when the vast majority of shows were still being shot like soaps and plays is something remarkable.

For people who aren't obsessively nerdy about the mechanics of TV production in the 1970s, the below will seem like nonsense and gobbledygook. However, it does set the scene nicely as to why Tinker Tailor stands out in the programming landscape, not just at this time but today. Back in the late 1970s, TV production was usually made in a hybrid format on both BBC and regional ITV stations - the majority of a programme would be shot in studio, on videotape, in a multi-camera format that a vision mixer would cut together to create an edit almost as the drama was being recorded. Indeed, only about fifteen years previously, programmes were recorded in order in one near-continuous block - very like staging a play without an audience. Five years before that, it was routine to broadcast dramas live. The only concessions to this rigid structure were filmed inserts - generally done if an exterior location needed to be represented or for something that would have been difficult to stage in a highly pressured recording block at Television Centre. These, however, were shot on film - generally, 16" - as it was impossible to take the bulky videotape cameras on location. By the late 70s, there were OB videotape cameras, but these were generally reserved for news, current affairs and sports programming, although shows like Doctor Who occasionally were able to take advantage of them for serials that relied upon the use of Colour Separation Overlay (CSO - an effect difficult to achieve on film), which, in modern terms, is analogous to greenscreen. It was incredibly rare for a drama to be shot all on location and all on film - that was seen as something prestigious and highly valued. The only significant exceptions were the work of ITC, ATV, and Thames and one BBC series we'll return to.

ITC's The Prisoner being filmed, with Patrick McGoohan in the title role.

In the 1960s, shows like The Avengers, The Saint, The Prisoner and the works of filmmaker Gerry Anderson all enjoyed the luxury of working with film. Generally, this was 35" film, which was higher quality than the 16" used for inserts. They were able to take wide advantage of location filming where appropriate (other than The Secret Service, none of Gerry Anderson's Supermarionation shows were appropriate for location filming), enjoyed a single-camera set-up, allowing better framing of shots and creative camera work, and, most significantly for the 60s, were able to enjoy colour filming long before it became standard. However, they were expensive to make and had to reap that success back. Fortunately, the colour and high-quality film made them perfect exports for the American market, which enjoyed a higher quality of television production than the relatively cheap BBC model. Some of these shows got the American showing they were after - The Avengers, especially, became one of the UK entertainment industry's greatest exports for many years. Others weren't so lucky. (Thunderbirds, Gerry Anderson's most successful and, arguably, best series, found its second series scuppered when Lew Grade failed to sell it to America despite its domestic success.) This practice continued into the 1970s with The Persuaders, The New Avengers, and, most notably, The Sweeney. However, there was less of an eye on American sales for these shows. Now, it was the view that film series were more popular with domestic audiences and allowed for dynamic, pacy programming that multi-camera, videotaped shows couldn't replicate. However, the BBC was still relatively behind the times. Before now, all filmed dramas were an extreme rarity - it wasn't how the BBC did it, so they didn't do it. One of the most notable exceptions was Jon Pertwee's debut Doctor Who serial "Spearhead from Space" - which was only done because the producer had anticipated a strike, and the show went back to the same old format for the next serial. However, when the BBC was producing a rival show to the gritty Sweeney, the producer of that show, Philip Hinchcliffe, insisted that if they were to do it, they had to do it all on film. And so, Target was born. However, it was still an outlier in the BBC's output - and it would have been incredibly rare for any adaptations of famous novels to be shot all on 35" film.

So, the above sets the scene for where drama was when Tinker Tailor Solider Spy was made. And, considering how acclaimed the series has become, it's incredible to think that when the series was first broadcast, it was put out on BBC2 - not a prestigious launch on BBC1. What did help the show was that it was broadcast towards the tail end of an eleven-week strike that took the BBC's only competitor, ITV and its associated franchises, off the air completely. This left open the possibility of the series finding a wider audience - BBC2 was, to some degree, still seen as a relic of the old BBC's mandate to provide educational and arts programming that, to the general population, it was believed wasn't of substantial mainstream interest. Thanks to the strike, however, Tinker Tailor Solider Spy did, indeed, have the chance to find a wider audience, and it did. The show proved so successful that it ended up becoming the but of a joke on Larry Grayson's Generation Game - at the time, one of the most-watched Saturday night programmes, pulling in audiences of around 25 million around that time. And, in the years since, that reputation has only increased, as, thanks to being shot on film in real locations, it has managed to age incredibly well. Indeed, watching the beautifully restored Blu-Ray today, it would be hard to distinguish from a prestigious mini-series of the time, other than in pace, aspect ratio, and the fact that the period details aren't period details but genuine hallmarks of the era.

Bernard Hepton, Ian Richardson, Michael Aldridge and Terence Rigby as the four major suspects: Poorman, Tailor, Tinker & Soldier.

Opening with a primarily silent shot of four men arriving for a meeting, you get the sense, from episode 1, scene 1, that this isn't going to be a drama that rushes its way to answers. Instead, it takes time to peel back the layers of deception and double-crossing, but not in a way that ever makes you feel like it is time wasted. Take the aforementioned opening scene, for example. On the surface, it just looks like a dry scene of people entering a room for a meeting. But, what writer Arthur Hopcroft and director John Irvin are cleverly doing is setting up each character without you even realising it - which, as more of the plot unfolds, makes you realise that you already know these characters without having to be brought up to speed with painful expository dialogue. (Although there's a little bit of that, don't forget there was a whole week between episodes, unlike in our streaming boxset era, and it is, mostly, integrated well into the flow of the story.) Each of the players has quirks and foibles: one is prim and proper, laying their files and folders out in neat order; one works very much on the move, chain-smoking their way through meetings and, indeed, through life; one isn't bothered by anything other than their tea. These little details help set up each of the four people who, it turns out, will be key players in this tale. Of course, there are five potential moles in British intelligence: Tinker, Tailor, Soldier, Poorman and Beggerman. While the first four are seated around the table, we meet the final potential traitor in a very different manner.

George Smiley might be one of, if not the greatest, of all Alec Guinness' screen roles. I know in more modern times, his most enduring role remains that of old Obi-Wan Kenobi in the Star Wars franchise, but his turn as Smiley, both here and in the sequel series Smiley's People, is a masterful example of an actor turning himself into a character before your eyes. Guinness first does a fantastic trick in the second episode and repeats it in subsequent episodes with Smiley's glasses. When he's speaking to someone, he'll clean his glasses, chatting genitally with them about something or other, and then, when he's finished, he'll put them on, and then his face drops. And all of a sudden, Smiley has gone from the unassuming, mild-mannered man to the Inquisitor General. His hard-set face becomes a wall against which all excuses, all protestations, all lies, fall by the wayside. It's a trick that allows you to see the two sides of the man and lets you speculate on which George Smiley is an act and which is the real man. With the glasses, without the glasses, or neither? That's the second question that runs throughout the drama (obviously, the first one is who the spy is, which, if you're following along with even just a bit of nouse, you can work out who it is), and there is an answer, but do not expect it to spell it out to you. Guinness makes the drama what it is, and he helps to ground the thing in mundanity while, at the same time, bringing a star quality rarely seen on British TV screens at the time. (Only Roger Moore was in the same league, and he hadn't been seen on screens for nearly a decade by 1979.) The idea of so-called film stars doing prestige TV might not seem that strange nowadays. However, back then, it was unheard of, and Guinness could only do it because of the vast amount of money he was making off the back of Star Wars. But it's one of the reasons why Tinker Tailor Soldier Spy stood out from every other TV drama at the time - because, despite having star talents like Michael Jayston, Iain Richardson, Beryl Reid and Sian Phillips, Guinness takes the whole thing to another level.

Terence Rigby and Alec Guinness as Roy Bland and George Smiley.

As many have said, the spy world depicted in Tinker Tailor Solider Spy is far from the glamour of James Bond or The Saint - or even the surrealist expressionism of "The Ipcress File" or The Prisoner. In fact, probably the closest TV equivalent I can think of is ABC/Thames' Callan: a show that, similarly, took a dim view of Bond's gimmicky gadgets, luscious landscapes and wonderous womanising. Spying is a grim business, and there's barely any glamour in the series - something befitting Britain during the so-called 'winter of discontent'. (Which was coming to an end when the series was filmed) The house where Smiley meets Ricky Tarr might have been grand once, but now, it's gone to wrack and ruin: the outside is crumbling, while the inside is sparsely furnished, with little more luxury than a few chairs and some plasterboard on the walls. There's an inordinate amount of time spent in grubby hotels waiting for contacts to turn up or to have what the old boys in the business might have described as 'a quiet word'. The offices of the Circus, the intelligence outfit at the heart of the story, are grubby, narrow and dark. These examples perfectly illustrate the series' use of place and setting to confer symbolic meaning. At this point in time, in the post-Swinging 60s, pre-Thatcher boom of the 80s, Britain was struggling. Financially, the country was on its knees - just three years prior, the IMF had bailed out Chancellor Denis Healy, and strict tax and spending controls were imposed on the country to recoup the debts. Britain's foreign influence was in a terminal decline - the country had finally been persuaded in 1975 to enter the EEC, while the loss of the empire throughout the 1950s and 1960s had resulted in Britain losing vast swathes of territory it could no longer afford to keep. Even culturally, Britain was being outstripped by America - Star Wars, Jaws, Greece and Close Encounters of the Third Kind were winning big at the box office, shows like The Dukes of Hazzard, M*A*S*H, and Starsky & Hutch were capturing more attention than home-grown British programming on both sides of the Atlantic, and the music charts were dominated by disco acts like CHIC, Gloria Gaynor, The Village People, Sylvester, Anita Ward, Earth, Wind & Fire, The Jacksons, Rose Royce and Donna Summer, among others, who honed their craft in the club scene of New York, San Francisco, Detroit and other American cities. Britain no longer had an identity, or at least, it no longer had a clear sense of its identity and its place in the world, and Tinker Tailor Soldier Spy reflects this. It's a drama about people who are lost in a failing state and are either blind to the house falling down or seeking to exploit its collapse for their own ends. Those who are calling out what's going on get chucked out: Smiley and Beryl Reid's Connie Sachs are pensioned off so they can cause no more trouble; Control is pushed over the edge, to the point when the series begins proper, he's already dead; and Jim Prideaux has gone into hiding at a boys' boarding school, not wanting the authorities to give him yet another 'quiet word'. Those desolate landscapes I talked about at the top perfectly reflect Britain and, indeed, the Soviet Union at that time, and the stark use of film and real locations, not studio sets, highlights this.

Across its seven episodes, Tinker Tailor Solider Spy presents the grim reality of Britain in the 1970s, using place and character in a way never before seen on British TV up to that point. Thanks to the luxurious production values afforded to it, plus the power of getting a massive film star in the title role, it remains one of the BBC's highest-quality and most well-respected dramas. And it is a testament to those making the show that it remains as culturally relevant, interesting and complex as it was back in 1979.

Alec Guinness as George Smiley.

Tinker Tailor Solider Spy is now available on Blu-ray and can be streamed on BBC iPlayer. All Tinker Tailor Solider Spy images are copyrighted to the BBC. The Prisoner image is copyrighted to ITV.