Though it won’t efface fond memories of the superb 1979 mini-series starring Alec Guinness, Tomas Alfredson’s adaptation of John Le Carre’s classic Cold War novel is a superb adaptation of a brilliant book, made with the same sort of fidelity, care and intelligence as the longer version was.

Gary Oldman fits nicely into Guinness’ old overcoat as George Smiley, the quiet, owlish agent of “The Circus,” as Le Carre dubbed MI5, who’s put out to pasture when a very secret operation of his long-time boss, Control (John Hurt), blows up in Budapest, leaving man-on-the-scene Jim Prideaux (Mark Strong) an apparent casualty. His job was to make contact with a Hungarian turncoat who was going to reveal the name of a Soviet mole at the highest level of British intelligence, but when the operation went sour, Control and Smiley were both canned.

Their departure leaves The Circus in the hands of four men. The new head is Percy Alleline (Toby Jones), beloved of the politicos like Oliver Lacon (Simon McBurney) because he’s landed a Russian source so secret and productive that Percy will reveal his identity to no one. The others are beefy enforcer Roy Bland (Ciaran Hinds), gregarious womanizer Bill Haydon (Colin Firth) and nervous Hungarian-born Toby Esterhase (David Dencik).

Smiley is reluctantly lured back into the game when it appears that Control was in fact correct, and he’s asked to lead an investigation to uncover the mole—who might be any one of the quartet now running the show. He’ll be aided in his dangerous operation by young Peter Guillam (Benedict Cumberbatch), and will get valuable information from Connie Sachs (Kathy Burke), an analyst also dismissed from The Circus after years of service, and Ricki Tarr (Tom Hardy), a sometimes reckless agent with secrets of his own, most notably involving a would-be defector named Irina (Svetlana Khodchenkova). A Russian diplomat named Polyakov (Konstantin Khabensky) will prove central to unraveling the case, and looming over it all is the spirit of shadowy Soviet intelligence chief (and long-time Smiley nemesis) Karla, here glimpsed only in passing.

The plot Le Carre concocted is a complex one, and even though scripters Bridget O’Connor and Peter Straughan have done an expert job of adjusting it to the compass of a two-hour feature and Alfredson and editor Dino Jonsater make skillful use of flashbacks to elucidate it, those unfamiliar with the book and miniseries may have trouble following all the twists and connections, and even those who are will need to concentrate in order to keep up. But the effort is worth it. Without resorting to mindless, frantic action Le Carre constructed a tight, cerebral puzzle in which even the apparently irrelevant plot thread about Smiley’s love for his philandering wife finds an important place. And he peopled it with vivid characters, not least the reserved, world-weary Smiley himself.

Alfredson and company have captured the texture and mood of the book superbly on screen. The unhurried place the director and Jonsater cultivate, and the grim, gray Cold War ambience in Maria Djurkovic’s production design, the art direction by Mark Raggett, Tom Brown and Pilar Casali, Tatiana MacDonald’s set decoration and Jacqueline Durran’s costumes reflect the novel’s dour spirit perfectly, and Hote van Hoytema’s cinematography packages it all in images that make sensitive use of light and shadow. Alberto Iglesias’ subtly suggestive score adds to the atmosphere.

Although Oldman sometimes seems to be channeling Guinness, he gives Smiley his own distinctive color, and the supporting cast all savor their moments in the sun, with Hurt and Firth, in particular, seeming to relish their roles and Jones and Burke taking the opportunity to play to the gallery spectacularly.

Just as Le Carre’s Smiley trilogy represented the class of the genre on the printed page, so Alfredson’s film puts other spy movies to shame. This is the real deal, and half-baked recent entries like “The Double” shrink even more in comparison with it. May we expect “The Honorable Schoolboy” and “Smiley’s People” to follow, please?