Can we talk for a moment about how amazing it is that a movie like this even exists? “Locke” is a beautifully controlled one-actor suspense drama. It is simply composed of phone conversations between the title character, Ivan Locke, and important people in his life. It takes place almost exclusively inside his BMW sedan as he zips along a nighttime English motorway. It carries us along, too, never coasting.

Tom Hardy often uses his husky frame to frightening effect playing violent men. In “Locke,” he’s cast against expectation. Locke is a construction manager, husband and father. A self-made man devoted to order and stability, he faces ruin as the result of a misjudged act of compassion. To set this life-changing mistake right he has deserted his job hours before an epic concrete pour to create a skyscraper’s foundation. On his drive, he juggles a series of cellphone calls — from his boss, a cop, a politician, his wife, another woman — that may offer him a second chance or tip him into the abyss.

Like a chess master playing a half-dozen simultaneous matches, his survival depends on his calm under pressure. The stakes are not quite as high as in last year’s adrift-alone double feature “Gravity” and “All Is Lost.” The only things at risk here are Locke’s career, his reputation, his family and his integrity.

It’s often possible to stave off personal catastrophe by acting selfishly. This man wants to do right by all his competing family members and co-workers, a much trickier task. Locke is determined to end the worst night of his life a better man than he was when it began.

Luckily, Locke is a lyric talker. Hardy speaks here with a melodic Welsh lilt. He talks his job-site assistant through the crisis by describing the monument they’re creating, a building that will cast a mile-long shadow, and the fragility of its base, a lake of liquid concrete “delicate as blood.” Between calls, he permits himself angry monologues directed at his late, despised father.

The disembodied voices on the line include Ruth Wilson as Locke’s aggrieved wife, young Tom Holland and Bill Milner as his confused, fearful sons, and “Sherlock’s” Andrew Scott handling the comic relief as his anxious underling.

Writer/director Steven Knight gives his story the sustained tension of a bank heist. That sense of forward momentum is a testament to his staging, his editing and his feeling for structure and character. The film is shot with intimate naturalism by Haris Zambarloukos, washing the star’s face with chilly autumnal light.

Hardy is utterly engrossing as a man whose life is balanced on a razor’s edge. Over the course of 85 swift minutes he makes Locke deeply endearing without ever slipping into sentimentality. It’s a picture of a man who has been scraped raw by regret but who also reaches out to the chance for rehabilitation. His trip carries us to a place we never would have expected.