Who’s the only playwright capable of dreaming up this scenario?

A convicted man is about to face the noose. He complains that he won’t be executed by the country’s chief HANGMEN but has been assigned to the second-stringer.

Such a scene could only come from the brain of the ever-so-crazy (that’s a compliment) Martin McDonagh. If anyone else has this much imagination, he or she isn’t writing plays. Once again via HANGMEN, McDonagh shows us he’s sui generis.

Although getting a ticket to HANGMEN during its current run at the Atlantic Theatre Company is about as easy as licking your elbow, all those turned away can take heart. An extension until March 25 has just been announced. Here’s hoping that Broadway and many Tony nominations follow.

As the lights dim, we hear a guitar’s bass notes, just as we did between scenes on SEINFELD – only these are ominous octaves lower. They do set the right tone for Hennessy, a condemned British man we’ll actually see hanged.

Hennessy insists that he’s innocent, which doesn’t cut any ice (or even crack it) with Number Two hangman Harry Wade. His unconcerned, all-in-a-day’s-work, matter-of-fact attitude suggests that anyone working in this field will eventually lose his humanity.

Case in point: Clegg, a newspaper man, brings up that first-stringer Albert Pierrepoint has killed many more than Harry. Our anti-hero’s response is that Pierrepoint had the advantage of being in the right place at the right time to execute World War II war criminals. “So,” he insists, “there should be an asterisk next to his numbers.”

To a certain generation or two, mention of an asterisk will bring back memories of Babe Ruth and Roger Maris. To anyone at all, it’s further evidence that McDonagh offers perceptions that wouldn’t occur to most everyone else.

Just before the execution, Hennessy vows that he’ll return to haunt Harry. When a McDonagh character makes such a taunt, you infer that haunting will soon be on the horizon. This threat hangs, so to speak, over the rest of the play.

Two years pass, during which time capital punishment has been outlawed in England. Harry, now the owner of a pub in Lancashire, is as much of a self-important person as he was in his previous position. With a hands-in-pocket ease, Mark Addy plays Harry with the entitled authority that Archie Bunker (whom Addy vaguely resembles) endlessly displayed in his home. He acts as if his wife Alice is not a partner in the enterprise but a mere employee. Imagine, then, the even lesser way he regards his teenage daughter Shirley.

Making a quiet entrance is Peter Mooney. He’ll take his time in establishing that he’s from London. That fact alone is enough to make Harry suspiciously stare him down and let him know he’s not welcome.

Peter possesses a good deal of Look-Back-in-Anger qualities, although he will be charming to Shirley. When he airily asks her to pour him any drink she thinks best, the way that she makes her decision reiterates that this girl of 17 is still a child.

Although Shirley is intrigued by the pub’s strange visitor, actress Gaby French doesn’t overdo her interest in him. As Peter, Johnny Flynn joins the long list of accomplished actors who have played McDonagh’s psychopaths. And yet, he finds humor in in one of his most benign moments, for after he says “I’m interested in sand,” the gesture that he gives is just as funny as the line.

McDonagh often seems utterly Godless, but he does ascribe to the belief that God is in the details. He notices the instances of everyday human experience that his colleagues miss. In Shirley’s first heart-to-heart with Peter, she makes a comment at the precise moment she takes a sip from her coffee mug. As a result, her remark gets lost in the echo that the cup causes so Peter must ask her to repeat it. That has happened in real life ever since people and cups were invented, but McDonagh is probably the first to put the moment on stage.

McDonagh often finds room for an older person in his plays; here it’s Arthur (an excellent John Horton). At times the pub patron provides the Voice of Reason, but just as often the Voice of Senility.

Yet the most colorful supporting character is Syd. He’s Harry’s former assistant who drops by and soon wishes he hadn’t. Harry reveals to all one of Syd’s missteps of years past; with more than an hour to go in the show, the poor soul is reminded of it time and time again (and time again). Whenever it’s mentioned, Reece Shearsmith is hilarious in showing his quiet exasperation that says he knows he’ll never, ever hear the end of it.

When one scene begins, Joshua Carr’s lighting alone makes us certain that it’s early morning even before Alice enters in her dressing gown. Once Peter returns, she exits; when she returns, she’s in the most provocative outfit that we’ll see her wear. Is Alice sexually interested in Peter? You never know what turn a McDonagh play will take.

Whatever dark impression we get of the playwright, McDonagh is capable of writing tenderly, too. Alice takes Shirley aside for a talk which is almost non-stop criticism. However, both in the way that McDonagh has written it and the manner in which actress Sally Rogers plays it, it comes across as constructive. Here’s a mother who truly loves her child and believes she can help her.

Most of the time, however, director Matthew Dunster delivers de rigueur high-voltage and high-wire-taught suspense. By the time that Peter tells the bar crowd that there’s “tension in the air,” we’ve already felt it for more than 90 minutes. Many pauses are long enough that even the slowest of perspiration glands will have time to catch up.

At one point attendees could barely breathe after Peter made a gaffe that was similar in type and intent to one that Trump recently made. They held their collective breath as they worried that McDonagh had gone too far. Perhaps – but McDonagh is smart enough to have another character come out with the perfect line to short-circuit our potential anger.

Although McDonagh obviously has a penchant for new comic concepts, he makes room for an old reliable. He could have chosen any of a thousand of authors for Peter to mention, but Kierkegaard was his choice, thus proving he knows that precept in the comedy writer’s handbook: words with ‘K’s’ are naturally funny. Leave it to McDonagh to give you twice as many in one word.

By the final curtain, you can decide if Hennessy’s threat has indeed been carried out or if sheer life has taken its inevitable toll — or if Harry has, as the expression goes, hanged himself.

Flaws? We’d expect at least one person to step in and protest how Harry decides to handle a difficult situation. Considering the comparative indifference shown by the barfly called “Inspector,” we might infer that he must have retired or the term is an ironic honorific. And yet there’s nothing to suggest either scenario.

Some who know McDonagh’s other plays may feel a bit disappointed that his ending here is very similar to one he used in one of his earlier masterpieces. Still, HANGMEN emerges as a wildly successful black comedy – although the play really requires a new color that’s much darker than black to describe it.