Poor New York City: so big, so diverse, and so theatrical, yet so difficult to capture onstage. The shows that do it best are, of course, musicals - the city sings and dances as part of its daily routine. But any old play can at least come close if it respects the people, the sound, and the heartbreaking whimsy that make New York like nowhere else. Unfortunately, though Eric Lane's new play, Heart of the City, which just opened at the Theatre at 30th Street, approximates New York's blood, it doesn't come close to finding its pulse.

This is despite a thoroughly egalitarian design that goes to great lengths to show how it's constructed from a wide variety of human molecules. There are two immigrants: a young gay man from Spain named Carlos (Scott Kerns) and an elderly Jewish woman named Sue (Marcia Jean Kurtz). An older man (Martin LaPlatney), Max, and an aging Brooklyn woman, Nola (Kurtz), spend weeks conducting a makeshift courtship on the 4 train. Sue's children, Lynn (Eliza Foss) and Bobby (Kerns), struggle to find personal and professional fulfillment as they watch their mother waste away from cancer. Lynn's husband, Michael (Mark Setlock), is emotionally crippled by not knowing his own father, but believes he's tracked him down on a park bench. And so on.

Each individual story gently interweaves with the others as everyone's lives cross in expected, incidental ways, but is essentially a self-contained playlet. But in his eagerness to depict so many different only-in-Manhattan types of experiences, Lane hasn't developed even one to any significant degree of richness. Worse, because the plotting is so general - does it matter that Bobby, rather than anyone else, is hitting on the gadget-store saleslady who's trying to convince him of the wonders of a vibrating armchair? - the show as a whole feels like a tepid collection of vignettes that wants to convince you without cause that Something Bigger is going on.

Ideally, that overarching theme would be expressed by the most important character in the play: New York City itself. But in neither Lane's writing nor Martha Banta's listless production does its personality come through in any real way. Bob Barnett's brick-walls-and-park-benches set does not exactly scream Manhattan, true, but the wobbly overall feel is the bigger problem. Exploring Sue's Eastern-European upbringing as Shoshanna (naturally played by another actress, Melissa Miller), Michael's uncertainty about his heritage, or Bobby's unrealized artistic inclinations aren't time- and place-specific ideas. Unless it's Lane's contention that New York is really just like everywhere else, this is not an effective way to particularize either the play or the city. As a result, neither has any identifiable flavor.

So it's not precisely the actors' faults that so many of the characters are so yawn-wrenching. Kerns stumbles into a few moments of charming ardor as three young men lost in the city's possibilities. And though Kurtz doesn't do much more than adopt different, stereotypical accents to distinguish between Nola and Sue, she finds a juiciness in her pronunciations that take her further than most of the other performers dare venture. Even Setlock, who usually provides a backhanded, working-man jolt to underfunded roles, broods through Michael instead of energizing him, doing little to convince us why his exploring his roots is such a vital pursuit.

The best explanation is the one that infuses Heart of the City in general: because they're there. But that's not much to hang a character on, to say nothing of a full play. As if to mitigate this, Lane has made Carlos the young, starry-eyed go-getter who describes his surrogate surroundings in excitable ways like "Here, there are so many of people, all of them run so fast!" But all the ones we see are dragging themselves through their days and nights, lost without the energy most shows and movies insist the city so readily imparts. Comparing that mythical New York to the real one could make a fascinating play, but there's no evidence that Lane intended that with his boring, downbeat treatment.

Heart of the City
Through June 28
Theatre at 30th Street, 259 West 30th Street, between 7th and 8th Avenues
Tickets online and current Performance Schedule: Smarttix