To those on the far side of 30, the question of whether two 20-something artists can remain friends after one of them gets a million-dollar book deal may seem a slender one on which to hang an entire play, but such is the premise of “The Four of Us,” the latest work by 30-year-old playwright Itamar Moses (“Bach at Leipzig”) to reach New York. Mr. Moses and his able director, Pam MacKinnon, however, counterbalance the preciousness factor by successfully re-creating a pulse-pounding state of post-college anxiety. For two would-be creative types still wondering if they will wind up selling insurance, questions like “Will my friend be more successful than me?” have an oversize, destabilizing power.

Ten years ago, Ben (Gideon Banner) and David (Michael Esper) met at a summer camp for aspiring teenage rockers. They went to different colleges but kept in touch, even sharing an apartment in Prague one summer. Ben became a struggling novelist; David, a struggling playwright. So far, so good. Then Ben rocketed ahead with his book deal, leaving David to wrestle with the notion that Ben has become richer, better connected, and more famous than he’ll ever be.

The play opens in an Indian restaurant, where David has brought Ben for a celebratory lunch. Mr. Moses then shuttles the action of this two-hander backward and forward in time, touching on the gentler past and the more acrimonious future. The nifty set by David Zinn has a bright-blue wall with four doors in it; behind the doors lie a shifting array of props and bits of scenery. For her part, Ms. MacKinnon keeps the staging interesting and sets a brisk pace. But though the surface of the play remains busy, the essential conflict between Ben and David continues to feel slight. The artistic aspirations of two privileged young men — and their need for praise and fame — may be tremendously important to them. But Mr. Moses never makes clear why these guys’ ambitions — and the continuation of their evidently flawed, fairweather friendship — should be similarly important to us.

The two-character conceit doesn’t help. Rather than deepening our understanding of the dual protagonists, the format limits it — we have no idea how David’s and Ben’s behavior around each other is different from their behavior around other people. The format also seems to circumscribe the story Mr. Moses wants to tell (especially when relevant characters are implied to be “just offstage”). This is never more evident than in a too-clever-by-half scene in which Mr. Moses pulls David and Ben into the lobby of a theater where, we are told, they have just been watching “The Four of Us.”

Not surprisingly, the play exhausts its jealousy theme pretty quickly. By the second half it has turned its attention to a perhaps more secretive corner of human relations: the tentative nature of friendship between teenage boys. The late scenes in Prague, where the boys uncomfortably compare their sex lives, and at camp, where they awkwardly admit their desire not to lose touch, are tender and poignant. In these moments, it feels as if Mr. Moses has stumbled onto his true subject: the importance and fragility of friendships between heterosexual men in a culture that is nervous about their intimacy.

Until May 11 (131 W. 55th St., between Sixth and Seventh avenues, 212-581-1212).