It’s a little chilling to realize that hired killer is a job that might be the world’s second “oldest profession.” Judging by the movies, most every culture seems to have them, and the way screenwriters depict them, they have traditions, mores, preferred weapons and a “code.”

That’s the intriguing premise of “Inkabi,” a South African/Zulu thriller about that continent’s most famous warriors taking their skills and tribal traditions into murder-for-hire. If the Japanese Yakuza, American and Italian mafia, the French, Brits and the Chinese of the John Woo universe can be contract killers, why wouldn’t South Africa’s bloody colonial and Apartheid history have produced hitmen?

But that promising set-up earns a lumbering, half-speed treatment in writer-director Norman Maake’s hands. Even the fights feel like rehearsals before “Action!” is shouted — walk-throughs that won’t fool most viewers.

A hit is contracted in a tiny, rural store/cafe out in Zulu country. And that ensnares a big city croupier, a axi driver, the cops and the object of that hit — a white man embroiled in a government scandal that’s made the newspapers.

Michelle Tiren is Lucy, a hard-partying, always-late roulette wheel spinner at the storefront Big Time Casino. Her drinking and snorting and loose-living have cost her custody of her daughter, we learn in the film’s laborious, melodramatic early scenes.

That court case guts her, and makes her say “Yes” to the creepy older customer (Jonathan Taylor) when he makes his second attempt to ask her out. She wakes up in his bed just in time to see him strangled, almost rituatlistically, by the scowling Inkabi nicknamed “Scar” (Dumisami Dlamini).

But that slow, deliberate taxi driver she stiffed on a ride the other day? He might be her salvation. Frank (Tshamano Tsebe) is a retired, gone-into-hiding killer. He and Scar know each other. They know “the code.” But unlike in the Chow Yun-Fat films of John Woo, it’s not “No women, no kids.” It’s thou shalt not harm or interfere with another Inkabi in his work.

Whatever the many melodramatic touches Maake ( “Piet’s Sake” and “Soldiers of the Rock”) serves up — kidnappings, every killer pausing and lecturing his victim before pulling the trigger, all but ensuring somebody else has time to fetch a gun and shoot the shooter in the back, he needed a fresh set of eyes editing this picture.

Maake pointlessly breaks the tale into “chapters,” and uses animation to give a taste of tribal history and the devolution into contract killing work.

But literally every scene drags in this Zulu contract killer thriller, with the camera lingering over many a take well past its payoff.

That underscores the weakness of the performances. Players don’t act Maake’s stentorian lines, they intone them.

“Money doesn’t change lives. It ruins them.” “I lost something today which I used to hold very dear,” follows declarations about “the power to lead people astray” and that deepest of deep thoughts, “Everybody is in a hurry to get something. You just need to wait your turn.”

Tsebe has more presence than charisma, and Tiren is more affecting than the character she is playing or the lines she delivers.

But even with the cachet of being a new world for Zulu John Wicks to inhabit, “Inkabi” just doesn’t play. It’s the “code” of hit-man thrillers that does it in. They’ve got to move faster than this, and the action has to reflect that speed most of all.

Rating: TV-MA, violence, nudity

Cast: Tshamano Tsebe, Michelle Tiren, Dumisami Dlamini and Jonathan Taylor

Credits: Scripted and directed by Norman Maake. A Netflix release.

Running time: 1:41