Helen Mirren masterfully portrays a British colonel faced with a decision to launch an airstrike. (Keith Bernstein/Bleecker Street)

Helen Mirren brings gimlet-eyed, tungsten-spined intensity to her role as a ruthlessly calculating British army colonel in “Eye in the Sky,” Gavin Hood’s taut, ­well-constructed thriller.

Unfolding almost in real time, this soberingly effective ­nail-biter follows the tactical, legal and ethical implications of a drone operation in East Africa that unexpectedly escalates from a surveillance job to a missile strike. And in Hood’s capable hands, what could easily be a talky, theatrical chamber piece turns into a dynamic work of cinema. The characters and the tense, increasingly dire dialogue drive the action of “Eye in the Sky,” with Mirren’s Col. Powell overseeing operations from a base in Surrey while she communicates with Kenyan ground forces in Nairobi, U.S. drone pilots in Nevada, a facial-recognition specialist in Hawaii, and a chain of military and political higher-ups in a paneled London situation room.

On the heels of last year’s similarly themed drama “Good Kill,” starring Ethan Hawke, “Eye in the Sky” exemplifies a new kind of war picture, defined by the remote targeting by unmanned drones and the eerily silent images of people in faraway lands being obliterated at the push of a button. The gamelike framing and composition lend themselves strangely well to the cinematic form. Rarely has the technology of war been so suited to a visual medium.

To his credit, Hood — who directed the Oscar-winning “Tsotsi” (2005) and the political drama “Rendition” (2007) — keeps a restrained hand when it comes to the optics, which here are used less for whiz-bang effect than to keep the audience firmly grounded in the movie’s myriad locations. He and first-time screenwriter Guy Hibbert are far more interested in the human elements in what becomes an emotionally gripping — if manipulative and schematic — life-and-death drama. (Viewers old enough to remember the Cold War tick-tock “Fail Safe” will sense a temperamental resemblance.)


From left, Francis Chouler as Jack Cleary, Jeremy Northam as Brian Woodale and Alan Rickman as Lt. Gen. Frank Benson. (Keith Bernstein/Bleecker Street)

While Powell pushes for a timely attack, a group of British cabinet secretaries and politicians second-guess her, worrying that any civilian casualties incurred would prove a political and publicity nightmare. Her intermediary in the argument is a quiet, subtly contemptuous general played by the late Alan Rickman, in a performance that proves how utterly singular he was. Whether he’s buying a toy doll, presumably for the birthday of a granddaughter, or making mordant observations about what he sees as pointless, bureaucratic dithering, his pitch is never less than perfect and sneakily on point.

“Eye in the Sky” is worth seeing if only to behold the actor in his glory one more time. (Rickman will reprise his role voicing the Blue Caterpillar later this year in “Alice Through the Looking Glass.”) But Hood has been just as judicious in casting the rest of the roles: Mirren combines both wile and steel in a masterful portrayal of Ahab-like obsession, while Barkhad Abdi — the Somali actor who played a marauding pirate in “Captain Phillips” — delivers a watchful performance as a surveillance expert in Kenya who expertly deploys a cleverly disguised menagerie of tiny, remote-control cameras.

There’s no question that Hood stacks the deck in “Eye in the Sky,” an anguishing piece of audience pandering that Rickman’s character acknowledges in one of his flawlessly timed asides. But even with that license, the filmmaker engages the audience in a worthy debate, in which the U.S. drone pilot — played by “Breaking Bad” alum Aaron Paul in an impressively reflective turn — serves as the most plaintive moral voice. In its own unsubtle way, “Eye in the Sky” makes a propagandistic case for drone warfare, if only in depicting the decision-making process as so thoughtful, agonizing and comprehensive.

Notwithstanding that inherent bias — and a tendency to caricature U.S. administration officials as far less thoughtful and painstaking — “Eye in the Sky” provides a valuable dramatization of what we’re asking of the public servants who carry out the missions we passively or actively endorse. This is the rare military drama that conveys both the graphic physical effects of war and its lingering psychic cost.

R. At area theaters. Contains some violent images and obscenity. 102 minutes.