A lot of people will recall the excellent BBC version of this John Le Carré narrative, notable for the performance of the late Sir Alec Guinness as the thoughtful "George Smiley." This adaptation is nearly as good, featuring Gary Oldman at his best in that part. What’s the role? Having recently retired, he's brought back by "C" (John Hurt) to attempt to locate a KGB agent hidden within MI6. As the story progresses, it becomes clear there are numerous possible culprits, and the well-written narrative presents us with memorable and suspicious situations that could be accurate, partially true, or simply misleading distractions! A strong group of familiar British actors enhances this intricate but not confusing story of deception and disloyalty. Tom Hardy, Colin Firth, and even Mark Strong, who isn't always remarkable, all contribute effectively, though I especially commend Toby Jones ("Alienine") in a truly reprehensible and ambitious portrayal, as well as Benedict Cumberbatch’s "Guillam." Tomas Alfredson has handled the film’s pacing skillfully. It might seem slow at times, but upon a second viewing, I noticed there was considerably more depth to some of the conversations, the subtle performances from the cast, and the meticulously created period setting. This demonstrates that restraint can certainly be an asset when the writing and acting work together, avoiding flashy special effects and visual spectacle.

Source on TMDB