A good deal of time has passed since we’ve had one of these plays visit off-Broadway.

I’m talking about the harrowing British import with angry young men who shine at being anti-social.

So in YEN, we get a good deal of yelling and violence mixed with head-banging against the wall, spitting in another’s face, a creative use of nose-picking, some casual transvestism and – need we add? — atypical sex acts.

In other words, anything so playwright Anna Jordan can get us to react.

YEN could almost make a seasoned playgoer who lived through the era of Harold Pinter’s THE BIRTHDAY PARTY, Edward Bond’s SAVED and Joe Orton’s LOOT a little nostalgic. Remember the days when we were inundated with such so-called cutting-edge, pushing-the-envelope plays?

Many theatergoers who haven’t had the history with this kind of shocker now greet YEN with the type of laughter that says “I’m hip! I get it! You can’t unnerve me!” Listen closely, however, and you might hear some hollowness and nervousness pervading the guffaws.

We’re looking at how the other .0000001% live – and let’s hope the percentage isn’t any higher than that – although a case can be made that Hench (Lucas Hedges) is more of a brooding young man than an angry one. We often hear that today’s youth have no attention span. Not Hench. His blank face rarely registers any emotion for many unceasing minutes at his PlayStation or the cheap porno that plays on his expensive TV.

It’s virtually the only furniture in the entire shabby room that has wallpaper curling down from the ceiling and up from the floor. There’s one chair, two lamps and a pull-out sofa bed that he and his half-brother Bobbie share.

With no bureau in which to store clothes, garbage bags must be pressed into service.

There isn’t much in them, anyway. Jordan establishes that the young men only have enough money to own one T-shirt between them.

(This does give those who appreciate male torsos to see at least one shirtless step-brother during most of the long first act.)

As for Bobbie, he’s more distressed than Mark Wendland’s set. You may never have seen a more hyperactive performance than the one that Justice Smith is giving in this MCC Theater production.

Pity Smith’s soles, which get a barefoot pounding time and time again as he literally jumps up and down, up and down, on the hardwood stage. Years from now, when Smith’s tibia and fibula are giving him grief, he might well rue the day he ever agreed to become a human jumping jack for Jordan and director Trip Cullman (who knows how to stage a ferocious play).

Every now and then Bobbie does calm down. Don’t miss the one time he takes on a fittingly sub-human posture when he sits in the precise way that a German Shepherd does.

At least then he’s quiet, which we’d prefer he’d stay instead of playing the ultimate childish game with Hench, repeating word-for-word what his half-brother has just said immediately after he says it, all to mock and infuriate him.

So here is a Ritalin-deprived man-child who talks loud and only quiets his voice when asking such thought-provoking questions as “If you could come on any part of a woman’s body, what would it be?”

It’s just another way in which he intently tries to establish his heterosexuality. “I hate gays” he blatantly states not long before he touches, embraces and wrestles with his half-brother. He even uses Hench’s toothbrush. You do the non-math.

Let’s be fair, though; when their mother arrives, Bobbie is equally affectionate towards her, smothering her with hugs. She’s Maggie, who has a most inelegant entrance when Hench and Bobbie carry her rag-doll-like body into the apartment while she’s in om a stupor that was either drink or drug-induced. After she awakes, she shows us where Bobbie gets his hyperactivity.

Maggie doesn’t look much older than her sons and acts quite a bit younger — or, more accurately, more immaturely. She continually defaults in her maternal duties and defaults in another way, uttering the standard-issue “Don’t talk to your mother that way!” in order to stop to an argument she knows she can’t win.

Ari Graynor is very skillful in showing that she does care for her sons; she just doesn’t want to be a mother, that’s all. When she tells Hench “You look just like your dad,” we can’t tell if it’s a compliment or a criticism.

None of the three cares too well for their dog, to whom they’ve given a name that’s meant to titillate. Jen (the able Stefania LaVie Owen), the young woman across the way, is more concerned in the way they’ve been “caring” for the pup. Whether Hench or Bobbie wind up treating her any better is what Jordan most wants to examine.

But a situation with one young woman and two young men? That’s a tale as old as prehistoric time. So’s a character such as Hench whose background prevents him from dispensing love. He often has his hands in his pockets when talking to Jen. With some people, this gesture indicates a casual assurance; Hench is trying to hide as much of himself as he can. We do somewhat admire him, though; that he isn’t as crazy as Bobbie is somewhat miraculous considering the close-to-total lack of parental guidance.

Jen could do with some love, too, and finds a willing ear in Hench. She even brings up that her father used to call her “Yen” as his own private nickname for her. If you think that Jordan is stretching things a bit to add a layer to her title, I’d agree with you.

Credit to Lucas Hedges for not throwing down the script after reading Act One and saying “What?! You want me for Hench? He’s a cipher who sits for most of the show reacting half the time, and not reacting the other half! There’s nothing in this for me!” True, Hedges hadn’t yet had his Oscar nomination for MANCHESTER BY THE SEA when he signed on for YEN, but he had to be somewhat discouraged when he reached the words “End of Act One.”

As it turns out, there’s plenty for him in Act Two. It starts with his dominating a long, potent but quiet scene – so quiet, in fact, that you’ll hear the Lortel’s heating system hard at work. Here Hedges ever-so-slowly but carefully lets us into Hench’s heart. Jordan does a nice job in peeling away each layer under the kid’s thick skin, allowing Hedges the opportunity to triumph, which he certainly does.

However, the action does return to Bobbie, whose story is ultimately far more dramatic. By this point, you may have assumed that the only acting Smith can do is overreacting. No — watch his controlled performance here. After one solid hour of being scared and repelled by him, you’ll now be moved by him.

Twenty years ago, Kenneth Lonergan gave us a harrowing play called THIS IS OUR YOUTH, whose characters did not do America proud. Is there any consolation in knowing that this is England’s youth, too? If you don’t find a happy ending in YEN, you may well be happy when it ends.