Closed Circuit

“Closed Circuit” starts out like it’s going to be a canny thriller about British lawyers uncovering the truth about a London terrorist attack, perhaps using the surveillance footage emphasized in the film’s opening moments and suggested by the title. But it turns out to be a disappointingly mundane, run-of-the-mill, this-conspiracy-goes-all-the-way-to-the-top sort of mystery, albeit a briskly watchable one. The surveillance aspect barely figures into it.

Directed by John Crowley (whose “Boy A” and “Intermission” are worth looking for), the film stars Eric Bana as Martin Rose, a defense barrister appointed to the case of a Turkish man (Denis Moschitto) arrested as the mastermind of a deadly bombing. The defendant’s “special advocate” — an additional defense lawyer, and I’m not going to pretend I know how the British legal system works — is Claudia Simmons-Howe (Rebecca Hall), with whom the newly divorced Martin had an affair. We’re supposed to find the barristers’ personal drama interesting, but it’s ordinary drama that has little bearing on the story. A newspaper reporter (Julia Stiles) puts Martin onto the idea that something’s fishy about the government’s open-and-shut case against the Turk, especially since some of the evidence against him is supposedly so revealing that to make it known — even to the defendant or his barrister — would be to jeopardize national security.

It quickly becomes one of those movies where people intensely say things like “What the hell have you gotten yourself into?” and “There are powers at play that neither you nor I can even hope to control!” Jim Broadbent stops by for a couple scenes to chew the scenery as the attorney general (which he is always welcome to do), and the story isn’t uninteresting. But the chilling questions posed by the Truth, when it comes out, aren’t well-served by the finale’s cop-out treatment of them, and the whole thing fizzles.

C+ (1 hr., 36 min.; R, some harsh profanity, brief violence.)