Machiavellian monsters aren’t what they used to be in the theater. The gloriously godless creeps that memorably rampage their way through the plays of Shakespeare, Jonson, Shaw and Brecht scale the dizzying heights of inhuman ambition and self-admiration. The closest contemporary American theater comes to that kind of mountain-sized ego is Roy Cohn in Angels in America.

Most of the time the stage serves up Nietzschean road kill, minor league flimflammers who, in the case of the sleazy journalist in Ronan Noone’s dark comedy The Atheist, proclaim their disbelief in God while following the well-worn path trudged by David Mamet’s foul-mouthed crooks and con-men, fleecing suckers and the competition on their way to scoring the American dream.

With The Atheist, Noone enters the pint-sized slimeball sweepstakes. Tabloid journalism is his duck-in-a barrel target; the image of the reporter as the fearless searcher for truth went out with fedoras and Teletype machines. Given how rapidly newspapers are losing their clout and circulation, the play’s corrupt scribbler, Augustine Early, would have been wise to play his trade on Cable TV news rather than the local rag. He would have become a star hack much faster. But everything about Noone’s snake slithering out of the trailer park — aside from his overripe name — is small scale.

The 80-minute monologue, stretched to the point of vaporousness, is made up of the confessions of the fame-hungry newshound Early, who sleeps, lies, and manipulates his way to temporary celebrity and fortune. He attempts to fascinate us with a blow-by-blow of his climb to the top. In the first half of the evening, before the character’s credibility runs aground, Noone’s inventive language supplies plenty of colorful crescendos (“silent conniptions boiling up inside”). His ink-stained creep is a zesty talker, a naughty boy on a vicious rampage, a white trash mercenary taking revenge on the upper crust.

Campbell Scott plays an underhanded journalist

Above all else, Early claims to be a consummate actor, juggling masks to exploit the desires and weaknesses of those he wishes to manipulate. When he hasn’t got his nose stuck in Early’s diary, Campbell Scott supplies a nimble portrait of an actor who is cheerfully deceiving everyone around him, including himself. Scott takes great pains to find some vulnerability in the character’s thuggishness. If only Scott were comfortable enough with the role to give Early the out-and-out exhilaration he demands. Perhaps that will come with time. The character wallows in the breezy zip of his sly dexterity, the bling of his delighted delusion that he is pulling off a high wire act that at any moment could end in failure. Scott is too restrained, given that Early is revelling in the mayhem he caused.

Early’s tawdry triumphs depend on a blackmail scheme involving the sexual gymnastics of Early’s actress girl friend, a voyeuristic congressman and his prim wife, and a pornographer who owes the reporter a favor. The machinations are titillating, but, given the junk the mainstream media is currently harvesting, goings-on are not particularly big potatoes, scandal-wise. (Though Hollywood imposed a moralistic ending, Billy Wilder’s film Ace in the Hole proffers a more chilling vision of American media decay. Now available on DVD, the film deals with a ruthless reporter, played by Kirk Douglas, who, for the sake of moving up the journalistic ladder, brings about the death of a man trapped in a mine cave-in.)

Also, Noone compounds the triviality of Early’s nastiness by trying to have it both ways. He sentimentalizes his soullessly charming villain, hinting that buried deep beneath his callous indifference to humanity throbs the heart of a disappointed idealist. But the attraction of no-holds-barred ambition on stage is that it taps into the audience’s dreams about how easily – if it could only toss ethics and conscience aside – power and riches would follow. Noone keeps trying to show there is sensitive side to Early, the product of an inner child denied the love he needs, but the figure’s yearnings for love and marriage are unconvincing, perhaps only another part of Early’s game.

Noone even evokes the granddaddy of overreachers, Shakespeare’s Richard the III, when Early crows about how he pulled off an impossible seduction. He sleeps with the wife of a man he has helped push to an early grave. But Richard acts out his disdain for humanity with panache, and his solipsism is icily untouchable to the end. What’s more, we get a chance to see him woo and win Lady Anne. Early describes his conquest and Noone’s words buckle under the strain of suggesting that, underneath the opportunism and sexual thrill, love is somehow involved: the yarn comes off as phony, especially given the reporter’s flimsy story about how the two break up.

Ultimately, Noone takes refuge in a-wink-and-a nudge moralism. Early reaps some of what he sows, though you never quite know how much of what he says about his meteoric career is for real. How can we trust Early? He may be inventing himself in front of us. Perhaps the details about journalism that don’t ring true and the unbelievable turns Early’s stories take are some sort of a giveaway? Hubris, like everything else, is being downsized. The Atheist gives us a man who is a monster in his own mind and, despite Noone’s invigorating way with words, it’s a mirage that wears out its welcome.

The Atheist Presented by the Huntington Theatre Company at the Calderwood Pavilion, Boston, MA, through September 30, 2007