It is my personal belief that one of the greatest challenges an actor can face is that of making stoicism into compelling drama. The term actor definitionally refers to one who performs an action, and remaining stilly stone-faced can sometimes come off as the absence of a thing rather than a thing itself. Riz Ahmed spends long passages of Darius Marder’s arresting new character study “Sound of Metal” stewing in the surly, resentful silence of the furious-yet-resigned; a fragile self-control punctuated by outbursts of rage and violence. When expressionless, he doesn’t fall back on the things actors do to make dialed-back emoting more active; no darting eyes, no twitch of the eyebrow, no sorrowful slow blinking. He’s defeated, spent, lacking the energy to say or do — or, he fears, be — much of anything.

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Ahmed locks into something extraordinary as Ruben, a man afraid that his carefully constructed version of stability is coming apart. He’s got a good thing going, touring small-town America with his girlfriend Louise (Olivia Cooke) as the metal duo Blackgammon. In the morning, he makes breakfast smoothies in the cozy travel trailer they share as a home, and in the evening, he pulverizes his drum set onstage. The senses of routine and purpose these activities bring to his life do a lot to keep the four-years-clean addict on the straight and narrow. He needs these shows as a safer outlet for his self-destructive impulses, like the chewing gum someone less hardcore might trade down to from smoking cigarettes. At least, that’s what he thinks, until he spontaneously goes deaf one day and his world comes crashing down around him.

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To say that Ruben’s replaced his heroin with an addiction to drumming would be putting it a little broadly. He’s transferred his punishment impulse, playing shows without earplugs to hurt and numb in the same way heroin might’ve once done the job. Marder conflates these tendencies as dual expressions of the fault lines in Ruben’s personality, both stemming from an inability to be alone with his thoughts. He’ll soon enroll at a rehab center inside a deaf community, where his wise, wizened sponsor (Paul Raci) will tell him that he looks and sounds like an addict as he talks about getting a cochlea-bypassing implant by any means necessary. He does, as anyone willing to sell everything they hold dear just to put some money together does too.

The film’s elaborate and expressive sound design sets it apart from the majority of warts-and-all stories about addicts in recovery by placing the audience in surrogacy with Ruben’s pain. The early concert scenes bombard viewers with walls of high-decibel noise so intense that one man at the Toronto International Film Festival premiere fainted and had to be rushed to the hospital. Marder’s approximation of partial deafness and the garbled facsimile of hearing offered by the implant is intimate and agonizing, the former dulled just past the point of coherence and the latter crackly or piercing depending on the moment. We may share in Ruben’s frustration over the difficulty of communication — when he doesn’t understand what’s being said via sign language, the subtitles respectfully translating the rest of the movie for deaf viewers vanish — and the frustration of watching him make the same mistakes over and over again.

His journey to find inner peace brings him to Paris, where Louise is crashing with her father (an unexpected, soulful Mathieu Amalric) while Ruben does the full-isolation rehab program. It’s here, from a Frenchman who’s lived a little more life than he has, that Ruben gains some perspective on his own denial. This final section, perhaps the most affecting of the film, stands out by diverging from the neo-Cassavetes direction that makes the previous scenes so jarring and open-wound sensitive (if a bit overextended on occasion, totaling a run time of 140 minutes). Marder shoots in long handheld takes for maximum mobility that allows the actors a spontaneity in keeping with the loosely improvisational style of the dialogue. There’s an a-ha moment upon learning that Marder’s a close collaborator of Derek Cianfrance; this feels at times like “Blue Valentine” painted black.

Like Cianfrance, Marder believes devoutly in the power of actors and acting, preferring to get out of the way and let them show their stuff. Ahmed returns the favor by delivering career-best work by a wide margin, letting out all his ferocity and vulnerability as if from a freshly lanced boil. In the ‘70s, this would be Oscar-caliber stuff — there’s a bit of “Mean Streets” De Niro in his Method-trained pit bull demeanor — but today, he must settle for the adoration of the indie circuit. It’s not hard to imagine NYU instructors showing this to acting students as worthy of emulation. In the best possible way, we can see Ahmed putting in all the work. [B+]

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