Michael Fassbender plays a talented intelligence agent, something right in the actor’s skill range, as you can see from many of his films. He’s told by one of his higher up contacts in the agency that there’s a mole, a double agent, in his section—and the kicker is that his wife, also a spy, played by Cate Blanchett, is one of the suspects. There are four others, two women and two men. They all work together and know each other. Fassbender’s character, George Woodhouse, decides to expose who the traitor is through a series of games, verbal tests, and covert acts of surveillance.

Tom Burke and Naomie Harris are particularly fun as two of the spy suspects. Pierce Brosnan is on board in a grizzled old hand role as the agency section head. But the real star is—the script, by veteran screenwriter David Koepp. Koepp has worked with Soderbergh twice before, a director that allows him freedom to let loose. Black Bag is a film of surprising and witty dialogue. A lot of the scenes are just the characters talking back and forth in repartee fast enough to make your head spin. It has been dutifully promoted and reviewed as a thriller, but it’s really a game or a puzzle film, in which the story is a way of casually putting its seven principal characters through a conversational gauntlet where we (along with Woodhouse) try to figure out who’s telling the truth.

The MacGuffin is some kind of deadly software program called Severus, that the turncoat is trying to sell to Russia. Now, if you haven’t caught my drift yet, I’ll just say it: Soderbergh is playing with the idea of the spy film, making it a clever game, instead of trying to be, you know, realistic. We don’t know what this intelligence agency is, although it’s British, apparently. Kathryn, Cate Blanchett’s character, is a bundle of mysterious female espionage tropes from a host of movies, not a feasible real person. The same goes for everyone else, and especially Fassbender’s nerdy, intensely cerebral George, with his perfect memory and analytical skills.

Am I saying that Soderbergh is satirizing spy films? No. He loves them far too much for parody. He’s employing the spy film genre to have fun, and he and Koepp are employing it to also depict these important glamorous people, “big shots,” indulging in torrents of cynical devious wisecracks about each other. The movie doesn’t aim for stupendous. It’s too modest for that. In any case, there’s a particular pleasure to be had from trying to solve a very complex puzzle. Black Bag generously provides that pleasure.