It's easy to see why Gary Oldman received an Oscar nomination for his turn as George Smiley*. Much of the role required Oldman to observe and contemplate silently. Many modern actors would falter without dialogue, but Oldman's expressive face adds to the seriousness of the espionage. After all, accusing a coworker and friend of being a Russian spy is no laughing matter, so Smiley takes the job with appropriate emotion. There's no humor for him, no fancy cocktails -- just a man conducting research, interviewing, denying sleep as he searches endless documents for clues. The life of a British intelligence agent isn't filled with glamorous destinations and exciting car chases, but perhaps the intellectual search for a double agent is far more terrifying than the physical pursuit.
The second biggest star in the film is certainly the objects. From typewriters to tweeds, the sets and accessories scream 1970's. Beyond that, the sheer silence of the soundtrack really showcases the importance of objects: the shuffling of paperwork sounds deafening; the buttering of toast is elevated from simple act to condescending torture. Smiley's decision to get new glasses has absolutely no impact upon the plot, but the visual lingering on the identifier holds enormous meaning: he must look closer, have better eyes. This is especially true because the audience is left clueless throughout the entire investigation. We can hazard guesses about the mole, but we have don't have enough information beyond scowls and personal infidelities. We must trust Smiley as we must trust our own glasses to bring us to the truth. As a viewer, it's difficult to place complete faith in a character, especially when all information is withheld. Thankfully, Oldman's performance is convincing enough that he earns our respect and our faith.
The supporting cast also does a stunning job of recreating 70's London. Strong performers like Colin Firth, Benedict Cumberbatch, and Mark Strong show the diversity of the intelligence agency: all white men, true, but varying from suave ladies' man to bookish sidekick to roguish working man. The standout to me, however, was Tom Hardy as Ricky Tarr. Undercover, Tarr is the only agent to experience true action. He goes behind enemy lines, defies direct orders, risks serious physical harm, and falls in love. He's defiant of the hyper-intellectual, frigid, unemotional way that his colleagues run their lives; he proclaims, "I want to have a family. I don't want to be like you." Without this foil, the film would just be a bunch of older white guys side-eyeing each other; instead, Hardy brings back the humanity.
Certainly, there are ways that the film could have been improved. The 2+ hour run time requires emotional investment, and the slow pace may be off-putting to some viewers. The slew of tertiary characters can be difficult to keep straight (which is probably the point: they all think the same way, and it's up to Smiley to step outside of the Circus and uncover the truth). And, of course, some real clues about the spy's identity would help pique audience interest and quicken the pace. Expectation is everything with this film. If you think you're going to see an exciting British spy film, you'll probably be disappointed. If you think you're seeing a cerebral film that conjures a London of yore, you're in for a rewarding experience.
* Footnote: While this is Oldman's Oscar nomination, his catalog is lengthy and varied. I'd like to remind everyone that this man played Sid Vicious in the 80's. Let that sink in. Sid Vicious. Now he's nominated for a role that's the opposite of Sid Vicious. So dynamic!