An artist is someone who hammers the same nail, over and over again, so the old adage goes.

So playwright turned writer-director Martin McDonagh’s “Wild Horse Nine” is essentially his “In Bruges” on Rapa Nui, aka Easter Island. Two hard men, killers, “vacation” in the middle of a job on the island with “The Heads,” the mysterious statues that made this little Pacific paradise formed on the top of extinct volcanos.

The creator of “The Banshees of Inisherin” leaves Ireland and regular stars Colin Farrell and Brendan Gleeson behind this time. But he uses a geopolitical America-not-living-up-to-itself story, with his tale of two CIA killers not wholly removed from “Three Billboards Outside Ebbing Missouri.”

It’s too sunny to be as dark as “In Bruges,” but it’s almost as darkly comical, pairing up Sam Rockwell and John Malkovich in a funereal, bloody comedy of CIA agents who’ve engineered the about-to-happen 1973 coup in Chile taking a breather and taking stock of their unquestioned, violent and politically misguided lives.

Beloved character player John Malkovich has his best role in decades as Chris, an aged but not over-the-hill CIA gunman who counts the Congo, Guatemala and maybe The Grassy Knoll among his assassination credits. At 72, Chris is unfiltered to the point that he’s a danger to himself, giving away the fact that he and partner Lee (Sam Rockwell) are agents to two Chilean coeds (Mariana di Girolamo and Ailín Salas) and hinting at the coming coup to them, to boot.

Chris is forgetting things to the point where he has to leave himself “Memento” notes. But he’s playfully toying with the idea of writing his memoirs, telling tales out of school in voice-over narration into cassette recorders about democratic governments brought down by the global ruling classes of Wall Street, Washington, London and elsewhere. That’s borrowed from the late-career Walter Matthau comedy “Hopscotch.”

Lee interrupts him only to tell him to STFU in various ways. But their boss (Steve Buscemi in the best role he’s had in decades) is concerned and furious enough to take this “memoirs” threat seriously. If Lee can’t rein Chris in, well… And he can’t.

“I was killing people before you were born,” Chris barks, way too loudly for the Santiago airport.

Still, they’re flying to Easter Island to kick back a bit as they wait for their handiwork to bear bloody fruit. Just don’t correct them with your “indigenous” peoples’ words.

“It’s ‘Rapa Nui,’ not Easter Island.” And those “heads” Chris keeps going on about? The sculptures are called “Moai.” They don’t want to know.

Malkovich, playing a 72 year-old with guilt, regret and a drug habit, keeps a half-stoned quaver in his voice throughout. His performance is considered, bluff and amusing. Too old to flirt with coeds? Let’s shock the hell out of them, then.

One really appreciates Oscar-winner Rockwell’s skill as a master “reactor,” taking in his character’s longtime partner’s musings, diatribes and secrets leaking with a quick laugh, a studied scowl and whatnot.

Malkovich’s age seems off in a period piece set just 26 years after the CIA’s founding. But then, McDonagh doesn’t sweat things like including songs on the soundtrack that hit the radio years later and crediting footage from the Kennedy Assassination to “Super 8” mm film, which hit the market a couple of years after that.

But that doesn’t lessen the pathos of a story that’s really about the death of the mythology America has told its story in. If the Kennedy Assassination cost the country its innocence, having the CIA interfere in democracies and murder foreign leaders cost us any chance of believing “American exceptionalism” and the heroic righteousness of Superman’s creed — “Truth, Justice and the American Way.”

I am devoted to the films of Martin and his older writer-director brother John Michael McDonagh (“Calvary,” “The Guard”),. So even though “Wild Horse Nine” — yes, it has wild horses in it — isn’t up to the pathos of “In Bruge” or the darker-than-dark laughs of “The Banshees of Inisherin,” it’s still head and shoulders above any darkly comic thriller released this year.

And if McDonagh the younger keeps finding men to pair up in bloody-minded two-handers like “In Bruges,” I’ll happily watch him hammer that nail until he’s beaten it to the point of bending.

Rating: R, graphic violence, drug abuse, smoking, profanity

Cast: John Malkovich, Sam Rockwell, Parker Posey, Tom Waits and Steve Buscemi

Credits: Scripted and directed by Martin McDonagh. A Searchlight release.

Running time: 1:56