For years, the gold standard for savage physical beat-downs depicted on screen was Chan-wook Park’s “Oldboy,” whose most visceral scene is a long-held-hostage “hero’s” furious claw-hammer takedown of an entire gang standing between him and his enraged revenge upon his tormentor.

A couple of brawls in “RRR” surpass it in scale via epic fisticuffs, a lone policeman wading through the teeming masses of Colonial India. The furious fights in “Onk-Bok” and the slaughterhouse of “The Raid” made their mark. But “Oldboy” has proven hard to top.

A stunningly-realistic, pulse-pounding punchout at the climax of Kin Long Chan’s Hong Kong noir “Hand Rolled Cigarette (Sau gyun yin)” joins the list of tussles that come close to topping “Oldboy.”

Our hero, a military vet named Chiu, is trapped in a stand-off between gang leaders. Chambers have been emptied and blood has been spilled. And just as the dueling mobsters reach some sort of rapprochement, Chiu — out of desperation, self-preservation and an untapped reservoir of rage — lashes out.

He’s spent the entire film being pushed around, drowning in loan shark debt, unwillingly mixed-up in another lowlife’s getaway from a big drug theft, one more smuggling deal gone sour, all adding to his woes and the threats to his person.

“G.I. Chiu”(Ka Tun Lam) is also carrying guilt over what he has and hasn’t done to show loyalty to his old comrades.

So he’s got issues. He’s had enough. And these gangsters? They’ve been seriously effing around. It’s time they found out.

A prologue establishes Chiu’s late 1990s military background, a Hong Kong soldier with the British before the colony’s handover, denied a passport to emigrate, sentenced to a life of crime by his limited skill set.

His present-day hustle? Smuggling “lucky” and endangered Golden Coin turtles from Taiwan. Boss Tai (Ben Yuen) has to stake him on this deal. But Boss Tai doesn’t know that middle-man Chiu and smuggler Pickle (To-yin-gor) are partners, scheming to drive the price up on the boss and add to Chiu’s commission.

Chiu needs this deal to service an old debt. No one who tells him he needs to “find a girl,” settle down, can imagine how he lives — in a big apartment cluttered with the detritus of earlier deals gone awry. Our hero never heard Broadway impresario Billy Rose’s famous warning, “Never invest in anything that eats or needs painting.”

But native Chinese aren’t the only ones deep into crime in Hong Kong. The racist locals call South Asians “brownies,” and a couple of Indians — Kapil (Bitto Singh Hartihan) and his cousin Mani (Bipin Karma) — are in the drug dealing business with Boss Tai.

“Go back to your country” insults are on the tip of every tongue the minute a disagreement happens. Something goes wrong in their interactions, and next thing Mani knows he’s on the lam, leaving his nine year old brother to fend for himself as he waits for word from Kapil, who’s also gone underground.

A breathless foot chase is how Mani ended up in Chiu’s apartment. Chiu tries to work out a way to settle his debts via the hiding Mani without getting Mani or the both of them killed.

Kin Long Chan’s story shifts points of view — from Chiu to Mani to the mob that mistrusts one as it searches for the other. He loses track of the ex-military story thread, which probably was destined for a larger role in this story at some point in the script.

Still, there’s a glorious claustrophobia to the cluttered settings and the streets, rooftops and alleys Mani is chased through. And our first-time director knows that a proper “film noir” only gets labeled such if there’s fog, and he serves up a doozie of a payoff scene in the lowering gloom of night.

Lam’s stoic turn in the leading role helps underscore the John Woo influences here. There’s less gunplay, and no churches or white dove Christian iconography. But the grit and the violence and the “code” of Woo’s world seem intact.

The one funny line in this Cantonese (with English subtitles) thriller comes when Boss Tai thinks some outsider is crossing him right to his face, just not in his native language.

“You think I don’t know MANDARIN? I grew up on SHAW BROTHERS movies!”

The one lighthearted scene comes from Chiu having to fill in for his houseguest when the guy’s kid brother (Anees) is threatened with expulsion from school. No, Chiu’s not really “a relative” of this “brownie.” He proves it by grabbing the kid by the ear until he apologizes to his teacher.

“Realism” in a movie fight means every blow counts, nobody has supernatural powers of recovery from the kicking that broke a rib or two, the concussion that must have resulted when your head is bashed into furniture or the floor. The combatants stagger, bleed and have to will themselves to carry on, survive and finish what they started.

That’s what happens here, with “Hand Rolled Cigarette” earning a fine climax to a pretty tight and thoroughly-atmospheric debut from an actor-turned-director who looks like he knows what he’s doing.

Rating: unrated, graphic violence, drug content

Cast: Ka Tun Lam, Bipin Karma, Ben Yuen, Michael Ning

Credits: Directed by Kin Long Chan, scripted by Kin Long Chan and Ryan Wai-Chun Ling. An Edko release on Netflix.

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