The fourth wall in Locke is the windshield of a car, inside which a man with a superhero's name drives toward a destination that, like the many details of his personal and professional life, only becomes known to the audience through a series of fraught phone conversations. Ivan Locke (Tom Hardy) doesn't break that wall, though he does exit through the driver's seat door at one point in what comes as a relief from the film's deliberately punishing and sometimes artful theatricality. The voices on the other side of Ivan's calls notwithstanding, writer-director Steven Knight has handed Hardy a plum role in what's essentially a one-man production set inside what may as well be a cardboard box, and the actor dutifully pounds the sides of it with that intensely simmering mix of rage and pathos that's become his calling card.
A stickler for safety and propriety, Ivan accesses his digital rolodex via buttons on his steering wheel, and through chats with his wife, son, colleagues, and others, a narrative of the methodical Welshman's downfall comes into grueling focus. The structural engineer admits to his wife of an almost year-old and one-time-only affair, subsequently destroying his marriage. Opting to be by the side of the woman who's now about to have his child, he also loses his job, though his integrity is such that he spends much of his car ride to London ensuring that the next day's work (a foundation “pour” of concrete) goes according to plan. And to the woman he impregnated and whose nerves he struggles to assuage throughout the film, he will not tell her that he loves her, because if it wasn't already clear, Ivan is a slave to the truth.
In the way it slowly completes the picture of Ivan's self-annihilation, with the nuances of one phone call often illuminating the subtext of another, Knight's screenplay is thrilling in its prismatic composition. But the filmmaker's obsession with space is entirely limited to his boxed-in setting and the emotional fireworks the pent-up Ivan risks setting off throughout; his only visual signature is the easy effect of rendering passing cars as out-of-focus blobs of light. Worse is how Knight fills his script with plodding detours into symbolist terrain, equating Ivan's obsession with foundational concrete to his unresolved daddy issues, which are made maddeningly evident whenever he chats with his ostensibly dead paterfamilias, whom he imagines seated in the back seat of his car. It's this literalizing of the character's hidden self and his inability to master it that ultimately exposes Locke as the squarest kind of theater: drama therapy.