Just what is it that makes The Third Man so great? Beloved British director Carol Reed, working at the height of his considerable powers? Orson Welles in one of the most famous screen performances of all time? Or perhaps Anton Karas' zither score, which immediately establishes a distinct character of exoticism, intrigue, and fun that Reed consistently and wittily applies to his narrative? The answer, of course, is all of the above and much, much more, but I would argue that the key player rising above such esteemed company is Mr. Graham Greene, the celebrated novelist and screenwriter responsible for some of the snazziest dialogue ever imprinted on celluloid.

　　 Greene's story and screenplay, which he accurately described as "a comic thriller," is a gift that keeps on giving, with patter that's never less than brilliant. The Third Man's post-war exploits amount to a darkly romantic adventure for those who thought Casabalanca wasn't urbane or sophisticated enough. Mercury Theatre veteran Joseph Cotten is ideally cast as one Mr. Holly Martins, a self-described "hack writer" of dime-store Western pulp (like Death at Double-X Ranch and The Lone Rider of Santa Fe).（英语影评） Martins is an incongruous presence in the persistently old-world atmosphere of Vienna, but he's come at the behest of Harry Lime, a friend of twenty years and a man too slippery and charismatic to be refused. When Martins arrives to discover that Lime has been run over in an auto accident, the American novelist quickly discovers there's something shady about the story of Harry's death (something shadier yet than Robert Krasko's all-time-great chiaroscuro photography).

　　 What transpires is simply too good to relate in common prose (certainly Greene thought so): it simply must be seen. Suffice it to say that like so many British (and Wellesian) films of its time, The Third Man is populated with terrific actors whose magnetic presence mitigates any unlikely plot particulars. Lovely leading lady Valli (. Alida Valli) plays a Czechoslovakian actress wanted by the Russian police and, more importantly, one that loved Harry Lime not wisely but too well. There's also a coterie of incisive character actors: Trevor Howard beautifully limns the Claude Rains-esque role of Major Calloway; as Sergeant Paine, Bernard Lee conducts a master class in how to make a "minor" character major; Ernst Deutsch's Baron Kurtz crafts prime slime ("I've done things that would have seemed unthinkable before the war," he admits at one point); and Wilfrid Hyde-White plays to distracted perfection the amateur intellectual Crabbin (in a moment of inadvertant clarity, Crabbin refers to Martins as "Mr. Holly Martins from the other side"). The Crabbin subplot proves a remarkable example of the screenwriter's "Rule of Three," one that's a perfect mousetrap for Holly.

　　 Much of the character of The Third Man comes from the Babel that is postwar Vienna, with its uneasy international "cooperation" amongst American, British, Russian, and French politicos and enforcers. Martins' naivete in the face of it all quickly seems symbolic of the souring of Americans' blithe trust in authority as the shadow of "the good war" lengthened. At the heart of the mystery is a conspiracy of war profiteering and self-preservation that swiftly blackens Martins' once happily ignorant playboy spirit. Welles plays a master manipulator at the heart of Vienna's labyrinth: with a cat-that-ate-the-canary smile and a twisted justification ever ready, he's a narrowly sympathetic devil with only a trace of soul wrapped within his prestidigital skill at winning love and trust.

　　 Through it all, Reed proves a master stylist in complete control (despite unfounded rumors that Welles grabbed the reins when he felt like it). Reed's use of sound is canny: the wingtips clattering on cobblestones, the echo of gunshots in the sewers. And visually, Reed writes the textbook on location shooting in his use of Vienna, including the most elegant use of high angles, low angles, and dutch angles you've ever seen (the Ferris wheel sequence makes equally effective use of location and studio shooting, the latter an awfully clever visual answer to the dutch angles that preceded it). The final chase through the sewers is boldly shot and edited, and the film's indelible final shot is a masterpiece of world cinema that can be held against any film ever made. The same could be said of the entire film, an ingenious entertainment for the ages.