The public feud between Mary McCarthy and Lillian Hellman continues to warrant our attention long after its two vehement opponents have left the stage. To be sure, the nature of their dispute transcended the specific questions it raised regarding Hellman’s misrepresentation of her past. Truth versus mendacity, fact versus fiction, call it what you will–at the heart of their argument was one of the more troubling developments of the twentieth century, which has only intensified as we’ve moved into the twenty-first: the culture’s growing tendency to conflate fact with fiction, both diluting and polluting our reality.

In retrospect, the war between the Jewish leftist Hellman and the Catholic liberal McCarthy seems to have been inevitable. Hellman was a playwright and memoirist who clearly believed in a writer’s artistic license to embroider. Though McCarthy based some of her novels on her own life, she was a stickler–and ultimately a crusader–for the truth.

What might be viewed as their lifelong rivalry culminated in 1980, when McCarthy famously said of Hellman during a TV interview with Dick Cavett: “Every word she writes is a lie, including ‘and’ and ‘the.'” In spite of Hellman’s bringing a $2.25 million lawsuit against her, McCarthy has been vindicated over the years, as we’ve come to learn that the plaintiff indeed lied about any number of things in her ostensibly autobiographical trilogy: An Unfinished Woman, Pentimento and Scoundrel Time.

While the hyperbolic thrust of McCarthy’s remark would probably have proven indefensible in a court of law, Hellman’s charges never made it to trial–not until now, that is, via the playful and bitchy imagination of Nora Ephron. In Imaginary Friends, her new “play with music” at the Ethel Barrymore Theatre, Ephron has these grande dames of American letters confront each other in a handsome and stylish red set in hell, where they bicker over everything, from how often they actually met to how the play that contains them should be staged. (When a relatively sedate McCarthy asks if there really has to be music, the more flamboyant Hellman says, “Why not? We have musicians.”)

It’s both sad and ironic to realize that while Hellman’s own plays are produced with less and less frequency, Imaginary Friends is at least the third play to feature her as a main character, following William Luce’s Lillian and Peter Feibleman’s Cakewalk. (Neil Simon has written a fourth, Rose and Walsh, based on Hellman’s relationship with Dashiell Hammett; it is to begin previews in Los Angeles at the end of this month.) But then, as Robert Brustein wrote in his tribute to Hellman shortly after her death in 1984, “It may be that her life, with its strong alliances, combative courage, and abrupt domestic scenes, will eventually be considered her greatest theater.” And in a witty defense of his subject’s tendency to dissemble, biographer Carl Rollyson also emphasized Hellman’s sense of theatricality when he claimed, “She suspended her own sense of disbelief.”

Ephron herself is no stranger to the blurring of fact and fiction, having based her novel Heartburn on her marriage to Carl Bernstein, which she subsequently adapted for a Mike Nichols film of the same name. She is best known as a writer for the screen (in addition to Heartburn, she wrote the screenplays for Silkwood and When Harry Met Sally…) as well as a film director (Sleepless in Seattle and You’ve Got Mail). In view of her uneven script for Imaginary Friends, it comes as no surprise to read in the program that this is her first play.

Without really having anything new to say about either Hellman or McCarthy, Ephron has found a highly unusual way for saying it, via comic routines, music-hall numbers and old-fashioned vaudeville shtick. Her cartoony approach may seem inappropriately matched to such hardcore intellectuals, and it’s bound to offend literary purists. But even if the comic-book tone seems, at first, to trivialize Hellman and McCarthy, it ultimately brings them down to a human scale, where their foibles are writ large, enabling us to see that on one level their war really stemmed from the clash of two outsized personalities vying for public attention.

Besides, given her frequent lunges for the limelight, Hellman in particular began to resemble something of a clown–albeit an outspoken one–in her later years. Consider what is doubtless the most familiar, lingering image of her: donning a fur coat for a ubiquitous Blackglama ad that coyly asked, “What becomes a legend most?” (How, one wonders, did Hellman ever reconcile that ad with her famous remark for the House Un-American Activities Committee: “I cannot and will not cut my conscience to fit this year’s fashions”?)

When we first meet “Lillian” in Imaginary Friends, she assumes that same imperious Blackglama pose, with an extended hand elegantly displaying a cigarette. The play opens with her asking “Mary” if they ever met, and her being told that they had, “once or twice.” It quickly backs up to visit Hellman’s childhood in New Orleans, and then McCarthy’s in Seattle and Minneapolis, where we view pivotal developments that Ephron suggests prompted the first to become a lifelong liar and the second a consistent seeker of truth.

The narrative proceeds to jump around in time and place as we meet the various men in their respective lives, and observe their initial confrontation at a writers’ conference at Sarah Lawrence College in 1948, when McCarthy felt Hellman misrepresented the Spanish Civil War to some students. As it closes the first of two acts, the scene is actually–and quite humorously–played out twice, to accommodate their different memories of what transpired. The play climaxes with Ephron’s invented trial, during which Muriel Gardiner takes the stand to say that she was the real one who helped smuggle money to fight the fascists during World War II, as opposed to Hellman, who stole her story for the “Julia” portion of Pentimento and made it her own.

The one constant throughout the play is Hellman’s and McCarthy’s seething anger at each other. (“I ruined your third act,” says Mary. “I was your third act,” rejoins Lillian.) But in her attempt to appeal to the widest possible Broadway audience, Ephron tends to oversimplify some of the rather complex issues she was compelled to cover. What follows is a typical exchange:

Mary: I was the palest of pinkos…. I became a Trotskyite almost by chance.

Lillian: No one here even knows what a Trotskyite is anymore.

Mary: No one here knows what a Stalinist is, either. She was a Stalinist. Tell them what you believed.

Lillian: The Stalinists believed that a certain amount of bad stuff was part of any revolution, and that it would eventually stop.

Mary: And the Trotskyites believed that bad stuff was bad stuff and would lead to more bad stuff.

Such didactic catechism would quickly become tiresome if not for the wonderful delivery skills of Swoosie Kurtz and Cherry Jones. The offbeat comedian Kurtz portrays a brazenly haughty Hellman, and the patrician Jones plays a softer and more confident McCarthy. Though neither is giving what might be deemed an exact impersonation, each manages to evoke both the mannerisms and the vocal inflections of their real models with winning results. Though he only has time to present brief caricatures of his real-life counterparts, Harry Groener is equally effective playing everyone from Edmund Wilson and Dashiell Hammett to Philip Rahv and Stephen Spender. The production is also blessed with a first-rate ensemble of eight dancers and singers.

Although Ephron’s scenario is overladen with cinematic jump-cuts and transitions, they are smoothly accomplished by Jack O’Brien’s smart, staccato direction, which accentuates the theatricality of the enterprise. The evening is also nicely kept in motion by Marvin Hamlisch’s tuneful, pastiche score and by Craig Carnelia’s lyrics, which veer from being sophisticated and witty to pedestrian. As the tap-dancing, anthropomorphized “Frankie Fact” and “Dick Fiction” sing, with straw hats and canes, no less: “And since you’re comfortable with which is which/Some performances we pull a switcheroo/Fact may in fact be Fiction/Out of his jurisdiction/Sometimes in fact there’s fiction too.”

Fact versus fiction, real life versus artistic representation: Meaningful questions about the blending of art with life were asked by Neil LaBute in his last play, The Shape of Things, which focuses on a malicious art student who literally reconstructs–and disfigures–her boyfriend, in the course of turning him into her thesis project. In this somewhat formulaic drama, Evelyn, the student, tells us that arguments and differing opinions are necessary for growth. When she adds that “only indifference is suspect,” she could be speaking directly for the playwright who created her.

As with his first two provocative films, In the Company of Men and Your Friends & Neighbors, LaBute’s handful of works for the stage have been geared to shake up his audience by daring to explore politically incorrect positions held by customarily despicable characters. A good deal of LaBute’s sensibility can be inferred from his titles alone. An early play was called Filthy Talk for Troubled Times: Scenes of Intolerance, and his production company was named Contemptible Entertainment. Underlying all of LaBute’s work, however, is a deep-seated morality that stems from his Mormon heritage.

While many began to feel that LaBute was selling out to commercial success in Hollywood by directing Nurse Betty, his plays have continued to contend with a more subversive view of life. Bash: Latterday Plays featured three monologues, including one delivered by an unrepentant participant in a fatal gay-beating that’s recalled in all of its grisly detail.

But if Bash ultimately proved more clinical than dramatic, and if The Shape of Things forfeited the credibility of its characters to the rigid formulation of its ideas, LaBute’s latest play, The Mercy Seat, emerges as his best and most tightly written. Although he is here revisiting the overly familiar subject of marital infidelity, he is also breaking new stylistic ground for himself. By introducing us to two characters in the throes of an intense situation that remains mysterious at first, he captures the mood of early Pinter, when the Playwright of Menace was still at his most effective.

A two-hander, The Mercy Seat is finishing up its world premiere Off Broadway at the Manhattan Class Company Theater, in a superlative production directed by the playwright and starring Sigourney Weaver as Abby and Liev Schreiber as Ben. When the play opens, Ben is sitting on a sofa in a well-appointed New York loft. He’s apparently stricken and in a daze: He fails to answer his cell phone, which keeps ringing.

When Abby arrives, she’s annoyed that Ben is not answering his phone, and she becomes even more aggravated to discover that he failed to make an important call he intended to make the day before. Eventually, we realize that Abby is both Ben’s boss and his mistress. We also come to learn that this is Abby’s loft, that it overlooks the site of the World Trade Center, and that the day is September 12, 2001. Ben was on his way to the WTC for a meeting yesterday morning when he stopped off for a “quickie” with Abby, effectively saving his life.

No sooner were the Twin Towers down than Ben began hatching a scheme to turn the disaster into a “meal ticket” for their happiness: If he’s presumed dead, they can run off together, sparing his wife and daughters the grief of knowing that he left them for another woman. Ben’s proposal to flee forces Abby to re-evaluate their long-term relationship, and to uncover a good number of her own demons in the process.

For most of the play’s uninterrupted 100-minute duration, Ben comes across as just another one of LaBute’s selfish and contemptible males, albeit made vividly personal via Schreiber’s remarkably nuanced performance. (“This is a national disaster, yes,” says Ben, “until the next time the Yankees win the pennant, then we’ll all move on from there. Sorry, but it’s true.”) But given the unexpected phone call he finally makes in the play’s surprise ending–which will not be revealed here–both Ben and Abby are lent a complexity that LaBute’s characters are typically denied. The play’s brilliant conclusion also suggests a Pirandelloesque purgatory for its characters, as it replicates the opening: Abby has left, leaving a bewildered Ben alone on the sofa, not responding to his ringing cell phone.

In a preface to the script, LaBute described his intentions with this play: “I am trying to examine the ‘ground zero’ of our lives, that gaping hole in ourselves that we try to cover up with clothes from the Gap, with cologne from Ralph Lauren…. I hold the mirror up higher and try to examine how selfishness can still exist during a moment of national selflessness.”

In the same introduction, he also claims, “The work itself fairly spilled out of me and onto the page”–and it certainly feels that way, as it rapidly plays out in real time on the stage. It’s also perfectly realized by two of our finest actors, each of whom locates a new acting peak with The Mercy Seat. It’s a special tribute to both Weaver and Schreiber that we come to care deeply about what happens to Abby and Ben, despite their heinous views and actions. How curious it is that these fictional figures should become so painfully real for us, in contrast with the highly stylized portraits of the real Hellman and McCarthy in Imaginary Friends.