In recent years – recent decades actually – there’s been a glut of Irish plays, mostly written by young men, that concern themselves with the revenge gifted loners take on a society where no one seems to understand or appreciate them.

These characters usually dress in the fashions of the 1970s or even earlier. They live in a land without laptops, cell phones or text messaging, and they often speak in a hybrid west of Ireland accent that has been filtered through the legacy of J.M. Synge.

It’s hard to know what it is about the modern age that so repels our most famous contemporary Irish dramatists, but it’s a fact that the worlds portrayed by most of them can often seem to have stopped progressing somewhere in the last century.

So when a writer emerges whose modernity is self-evident it’s a major event in Irish theater. To be modern in Irish drama apparently means to be willing to get your hands dirty; to grapple with how life is lived now.

Most of all it’s about seeing the Irish working class as something more than poetic sad sacks or punch lines. The hardest job Irish writers have now is to move foreign audiences beyond the cozy 19th century classics they have grown to love.

In her new play The Last Days of Cleopatra writer and actress Laoisa Sexton paints a rock and roll portrait of modern Ireland that’s so vivid it leaps to life from the first scene.

Sexton writes dialogue that is so rich and redolent of modern Dublin that the first surprise of her excellent new play is that it’s happening at all. Like the working class Dubliners she loves and brings to life here, language in her hands becomes a tool to attack, expose, scorn, laugh at and hopefully defuse all the daily hardships of Dublin life.

In The Last Days of Cleopatra Sexton plays Natalie, a wayward and brilliant young Northsider who lives in mortal terror of magpies, who prophesy the doom she’s always anticipating. Like a lot of Irish people Natalie lives her life bracing for impact.

She has good reason to fear the worst, though. Her mother is in the hospital and her shiftless father is usually nowhere to be found.

Like her previous play For Love, Sexton’s Cleopatra is all about love. As in, where do you find it, how do you keep it, what does it feel like, how do you know? Because of that it stands in stark contrast to the aloof snark and cynicism of so much contemporary writing by Irish men.

The truth is that poor Natalie is so preoccupied with her feelings because (and she doesn’t allow herself to know this yet) no one else is. Sexton allows that awareness to emerge gradually.

As her flamboyantly gay brother Jackey, Michael Mellamphy resists the temptation to camp it up and instead gives us a sharp and conflicted portrait of a young Dubliner. Jackey is all about Twitter and put downs, the better to deflect you from the pain he’s experiencing himself. Mellamphy gives us a distracting show, but he gives us the heartache behind it too.

As Harry, the old show band legend who can only be relied on to be missing, the gifted Kenneth Ryan anchors the emotional core of the production after a shaky start that’s due to a tense split scene he shares with Natalie.

The truth is that Natalie’s rage and eloquence could sink a battleship, and each time she lets fly she threatens to overwhelm her opponents. That happens early on with her father, but Sexton then wisely banks her fire after that and allows the full family portrait to emerge in increasingly accomplished ensemble scenes.

Kevin Marron distinguishes himself as a series of brilliantly vivid Dublin types (including playing in drag) in scenes that conjure the fair city like few other contemporary writers can.

Sexton’s play deepens as it progresses, eventually resembling Paula Vogel’s The Baltimore Waltz in its tone and subject matter (both plays were inspired by real events in the writers lives).

The scene where Sexton’s blasted family travels in a hearse to their mother funeral takes an axe to the frozen lake of modern Irish playwriting. Here’s in one scene Sexton rescues us from the calcified portraits of ourselves that we’ve been subjected to for years.

The Last Days of Cleopatra is in its current state as unruly and brilliant as Natalie herself, but it’s a cause for amazement that a play this incendiary and implicating has been written at all. If you only see one Irish play this year, this is the one.

The Last Days of Cleopatra continues through September 7 at Urban Stages, 259 West 30th Street. For tickets call 866-811-4111.