Sitcomish action, unfunny running gags and heaps of sentimentality combine to quash the few glimmers of serious content in Joe DiPietro"s Over the River and Through the Woods. The shame of it is; it didn't have to be this way. DiPietro's subject — the relationship of a young man of Italian heritage to his elderly grandparents — could have led us to meditate on aging, the generation chasm, the breakup of the extended family, the inescapable school of time. And there are moments in Act Two when author DiPietro actually dares to address some of these noteworthy issues. But it's too little too late: After innumerable jokes about the heat in grandma"s apartment, the omnipresence of Italian food, and grandpa"s difficulty driving, we have little patience for belated solemnities. Add to this a group of performers who seem about as Italian as Mount Rushmore, and the result is an evening of discomfort and patches of boredom.

True, there are a few high points — some authentic humor, some honest psychology — but there are also too many gimmicks here, too much pulling at heart- and puppet-strings. The story of Over the River (which I saw in a preview) concerns thirtysomething Nick Cristano and his two sets of grandparents, Frank and Aida and Nunzio and Emma. All the characters in this family live in or near Hoboken, N.J., and all are painfully conscious that Nick's parents and sister have moved far from the old homestead, to Florida and California, respectively.

Respecting his grandparents' need to have some contact with the younger generation, Nick visits them every Sunday, consumes their lasagna and even joins them in the occasional game of Trivial Pursuit. But soon after the play starts, Nick tells his grandparents that he"s just been promoted — to a position in Seattle. The news creates havoc: The last thing these four want is to lose their cherished Sundays with darling (though occasionally hot-tempered) Nicky.

So the grandparents come up with a plan: to invite young and attractive Caitlin O'Hare to Sunday dinner in the hope that she'll ensnare Nick and keep him near Jersey. Will the ploy work? Will Nicky find in Caitlin reason to stay in the Northeast, or will he move to Seattle — perhaps even taking her with him?

Now, on the face of it, this same plot could be the occasion for a comedy of depth and real relevance. But DiPietro isn't truly interested in the important subjects his script alludes to, at least not as much as he's interested in manipulating his audience. So, aside from the running gags that I've already mentioned, there's the strategy of sentimentality: speeches about how poor someone was back in the old country, or how this grandpa met and serenaded that grandma, or how Grandma Aida "was Einstein" with 'a tomato, pasta dough and garlic."

Then there are the one-liners that aren't particularly funny. About Chinese food: "Thirty years ago, I had dinner at a Chinese restaurant. To this day, I have no idea what I ate." Or about ethnic Care packages: "I just mailed your sister 12 pounds of fettucine alfredo." Or about the ignorance of the elderly: "She"s a what?" "Vegetarian." "What the hell"s that?" "Animal doctor."

Of course, writing of this sort has no real meaning, reveals nothing that matters; it just calls out for the easy affirmation of audience laughter while distancing us from the characters who speak it. And when the dialogue does get serious — when we learn, for instance, that one of the grandfathers is secretly battling cancer — the moment feels so exceptional that we don"t know what to make of it. At best, we discover that DiPietro can write soberly after all. At worst, we remind ourselves that another silly joke can"t be long in coming.

The acting is partly satisfying, partly confusing. Fundamentally, these Italians don"t look or sound very Italian. The only actor who tries to speak with an Italian accent is Joe Buttram as Frank, and he"s far from convincing. Once we've gotten over wanting our ethnic characters to seem ethnic, though, it"s possible to enjoy the performances on their own terms.

Best of all is Rich Rice as grandfather Nunzio. Rice's Nunzio is gentle, self-deprecating, entirely convinced that "what matters is family," but too respectful of Nick's freedom to try to compel him to stay in town. Anne Benedict is also fine as Nunzio's wife Emma, a likable, dotty old woman whose idea it is to invite Caitlin to Sunday dinner. Mary-Lynn Ring as Caitlin is all smiles and goodwill, surprising us (and Nick) with her principles just after charming us with her surfaces. But Scott Leon Smith as Nick exudes stability when he should seem mercurial, and the usually excellent Mimi Rice is strangely tentative all through the play, as if reluctant to fully inhabit the role of Aida.

Rice's wonderfully realistic living-and-dining room set, though, or with Amy J. Cianci's up-to-date costumes. And Devin Preston's sound design tells us, with a couple of old songs, that the center of the story is the grandparents, not the grandson.

Even at its most manipulative, there's an admirable earnestness about Over the River, an underlying belief that what's being said is of great import. But a half-hour or so into the play, you can't help but realize that the inspiration here is more Henny Youngman than Eugene O'Neill, more Carol Burnett than Caryl Churchill. If television didn't exist, this type of comedy might find some justification; but as it happens, there's more emotionally powerful work on the networks, not to mention what's on cable.

Come to think of it, a show like Sex and the City makes Over the River and Through the Trees seem practically antediluvian. And a series like Six Feet Under makes Over the River seem to come from an older, vanilla universe, one where Freud never existed, Ibsen and Strindberg never wrote dramas, and at the deep heart of the cosmos was a slightly lengthy game of canasta.

Contact performing arts critic Mark E. Leib at mark.leib@weeklyplanet.com or call 813-248-8888, ext. 305.