In Jean-Stéphane Sauvaire’s “Black Flies,” silence is as scarce a commodity as hope. Young first responder Ollie Cross (Tye Sheridan) learns very early on that the job comes with two partners: the one sitting next to you and the relentless cacophony of sounds that cut through the vastness of night as shears. The thudding of bodies on hard concrete, droplets of blood drained from veins in large gulps, the crackling of bones as they contort unnaturally, the bone-chilling notes of guttural weeping, and, on top of it all, the maddening high screeches of an ambulance siren, death’s roaring precursor. 
A failed medical exam landed Cross in the New York City Fire Department, neither a dream nor a vocation, but a convenient night gig that would free the young man’s days to study to retake the exam while also allowing him to maintain contact with the medical practice in some form. Enveloped by the muted grey lights of early morning, the firefighter sits by a rickety desk in the corner of an even ricketier improvised bedroom in the home of a Chinese couple, his single book and bare surroundings placing him almost like a Paul Schrader anti-hero.
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Alas, Schrader, this is not, and “Black Flies” soon moves away from the mental downward spiral of its central character to lean towards a buddy movie when Sean Penn’s Gene Rutkovsky welcomes Cross as his night shift partner and mentee. A veteran firefighter who was amongst the PTSD-riddled first responders at 9/11, Rutkovsky, or Rut, is a well-spirited all-American guy who swallows the bitter pill of constant trauma by firmly holding onto the idea of servitude.  
Though violence is rarely seen in its active form, it still permeates the entirety of Sauvaire’s thriller, present in the bruises and cuts that mark battered and beaten bodies. New York is a mirror to the crumbling of its people, with Rut and Cross squeezing through the gritty underbelly of the town, breaking into apartments by the train tracks where floors are covered in dusty pieces of plaster, the walls blemished by gaping holes from where you can see the rusty old pipes that ooze the pus of the city into the homes of its citizens. 
“Black Flies” is at its most interesting when it leans on the concept of “Nightcrawler” by way of “Station 19”. When it drops the former in favor of the latter, however, it does away with the few gripping elements of its narrative —- the shallow yet engrossing attempt at a psychological study of a newcomer thrown into the merciless pits of the gig, the scars left by trauma on those who carry it on their tired faces, and the way the job tears apart the few loving relationships in the lives of those who choose to stick to it. 
Sheridan, for my buck, one of the most underrated young actors of his generation, adds yet another Hollywood A-lister screen partner (Nicolas Cage and Ben Affleck are amongst other established actors to almost fall second fiddle to their younger counterpart) to his sprawling resume, not only holding its ground against the overacting Penn but mostly overshadowing the actor-turned-producer-turned-war-activist. Sheridan is skilled in conveying distress through the rare moments of quietness in Sauvaire’s thriller, perambulating the streets of New York as a flaneur, finding solace only in the sleek — and almost permanently nude — body of his girlfriend, a young mother with the potential to offer him a coveted place in the warm nest of a well-regulated family. 
Coming through the sidelines to almost win the race is the always great Michael Pitt, here in the very Michael Pitt role of Cross’ angry foe, a barking man who chooses to become a first responder out of a rage-filled God complex. He prances around his new colleague as if permanently ready to pounce, growling at any sliver of goodness that might threaten the reign of terror he enjoys working under. With a face meant to terrify, Pitt’s big blue eyes pop against the saturated bright lights of nocturnal life, a savage wolf in search of his next prey. “I don’t know if I believe in heaven, but I believe in hell,” he tells the young cadet. It’s easy to believe in something when you’ve built it with your own bare hands. 
It is a shame, really, that “Black Flies” takes a sharp left turn from the frenzied Pitt madness to complete its painstakingly predictable journey towards establishing Sean Penn as the one true hero of sacrificial Americana, including a risible scene where our certified good guy takes a stance against domestic violence — a pointed choice given the actor’s past history of alleged abuse towards women. Oh well, if taken exactly for what it is, “Black Flies” offers plenty of nihilistic entertainment. But don’t be too tempted to look for any depth in a film far too comfortable in the formulaic confines. [B-] 
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