Writers and actors – perhaps more than any other artists – have fundamental commonalities. Both interlope. Both steal. Both look to their immediate surroundings for the character, the gesture, the voice that will make a story soar. Each has been known to plow ahead without much regard to personal casualties left in the wake of an artistic mission. And the result, if we are lucky and forgiving, is occasionally the stuff of real art.

In the two-person drama “Collected Stories,” which opened last week at Penobscot Theatre, Donald Margulies gives actors the chance to play writers, and the conflation suggests just how much the two careers overlap. But it is also about the tricky ways artists feed off one another. “Influence is simply a transference of personality,” wrote Oscar Wilde, and Margulies, who quotes Wilde in an epigraph to the play, pierces the drive of the artist and exposes the wily heart of an opportunist.

The “writers” in this story are Ruth Steiner, a veteran short story guru shaped by the Beat generation, and her protege, Lisa Morrison, an aggressive grad student who wants to find out if she has “the stuff” to be taken seriously. Finally, the play is about the tension between the master growing old and the apprentice growing up. By the end, they both suffer a painful loss, and the ruthlessness and vulnerability of ambition’s cheap tricks – or is it art’s triumphs? – are on the table.

Delivered in a series of meetings at Ruth’s Greenwich Village apartment over the course of six years, the play relies upon the engaging mental energy of its two performers to convey the alacrity of passion. On opening night, however, the show dragged its heels instead of kicking up the dynamic dirt between these two women. The script, which is alternately witty, insightful and preachy, does not comfortably sustain the three hours that director Mark Torres has allotted. The story itself can be challengingly static, but traces of sentimentality in this production threaten the drive of this duet-cum-duel of minds.

Fortunately, there are scenes that depart from the intermittently slow pace. Those are guided by the pert and prudent talents of Joan Jubett, as Lisa. She starts at such a high pitch that, at first, it seems as if her wide-eyed eagerness may not have any place to go. But Jubett is full of surprises, and an onstage freshness allows her to slyly posture herself for throwing some wickedly smart punches.

Her ring mate, Ruth Miller, as Ruth, is less convincing. She stumbled on a number of lines opening night, which detracted from the tension building between the two characters. Perhaps it’s only a matter of time before Miller combines her entertainingly wry manner with the innate dispatch and wisdom that are Ruth’s stock in trade. Miller gives hints of these qualities, and she can be winningly incisive. But in addition to the fateful predicament Ruth finds herself in, there needs to be something of the profundity that made her into the formidable authority she is.

Costume designer Gabriella D’Italia alternates between Beat queen and scholar for Ruth, and pretty much straight Gap girl for Lisa. The outfits are attractive enough but lack a downtown grittiness.

The real star of this show is the set, designed with an eye for “distracted intelligentsia” decor by Greg Mitchell, and assisted by lighting designer Karen Hornberger. Even though there’s no New York Review of Books – the bible and bane of writers in Ruth’s league – there are enough newspapers and magazines to provide both actors with handfuls of stage business in the show.

Penobscot Theatre will present “Collected Stories” through Nov. 18. For tickets and information, call 942-3333.