If you want to wield power in this world you’ll need a whip. You also need to be unafraid to crack it.

But just remember that, as Irish American playwright Eugene O’Neill outlines in the revival of his remarkable play "The Emperor Jones" now playing at the Irish Repertory Theatre, sooner or later that whip is going to be used on you too. Power always comes with a price attached, and it’s usually steep.

First performed in 1920, when it caused a sensation, "The Emperor Jones" was a revolutionary play in its time. To begin with it presented a black actor in the title role and then it placed him in a position of ultimate authority, even lording it over the white men who fear and loathe him.

It may be hard from this vantage point in time to understand what a provocation that sight was to many theatergoers even in New York in 1920, but the fact is that O’Neill was turning every convention of the era on its head. Black men were more commonly portrayed as shiftless stereotypes, and they were certainly never seen as powerful or threatening.

In the title role of Jones, actor John Douglas Thompson commands the Irish Rep’s stage like a Colossus from the moment he appears. Dressed in bright colored military garb and thigh high leather boots, he’s almost (but not quite) a caricature of authority, his appearance calculated to dazzle and amaze, all the better to prevent anyone from ever questioning his authority.

Douglas Thompson inhabits the role with such conviction that you wonder if he’ll ever emerge from it. To begin with he’s all swagger and poise, strutting around like the overbearing potentate he knows himself to be.

But as the play progresses the shadows that surround Charlie Corcoran’s superbly effective set begin to lengthen with what O’Neill calls little formless fears that begin to collect around him.

When the play opens Douglas Thompson’s character is -- unknown to himself -- about to make his last stand. The tom-tom drums are beating far away offstage turn out to be a warning that his number is finally up.

O’Neill seems to be considering the ways in which colonialism and violent resistance to it must always live in a tense standoff, which certainly speaks to the Irish experience, but there’s a racial element at work here that gives the play even more metaphorical heft, sometimes to the point where it can be difficult to discern the playwright’s ultimate intentions.

What’s never in doubt is the strength of this play or this magnificently realized production. In the modern theater most directors ignore a playwright’s stage directions. Indeed, it’s become almost an article of faith.

Nowadays the playwright’s notes are often blacked out, overlooked or even torn up because most modern directors believe that a script is just a starting point, a blueprint for the main event -- themselves. 

If given the choice between a living playwright and a dead one, most directors would pick the old masters, because that way they can reinterpret their texts without actually having to listen to them grouse about it. That’s why it’s almost a revolutionary act when a director decides to stage a play the way a playwright actually intended it.

And this is what makes the Irish Rep so special. Director Ciaran O’Reilly has respectfully hewn close to O’Neill’s original directions, and in the process he has helped to save the reputation of this challenging and staggeringly powerful work.

While it’s true that the dialogue of the play is dated in many of its terms and attitudes, the central themes -- the struggle for existence, the ruthlessness of man’s pursuit of power -- are as vital and compelling now as the day they were written.

Wisely, O’Reilly also trusts O‘Neill’s vision, and his additions -- longer dance sequences, puppets and a sound design that’s so effectively creepy that it eventually makes your skin crawl -- are all enlivening additions to an already effective play.

As the ghosts of his own past confront Jones the play achieves a raw atavistic power that will unnerve you. This production appears to have been years in the making, the result of a deep and prolonged philosophical engagement, and because of that it’s achieved a such level of artistry that it will literally leave you awestruck.

The Irish Repertory Theatre is located at 132 West 22nd Street. For tickets call 212-727- 2737. Engagement ends on November 29.