Remember that old Dylan song, “Somethin’ is happenin’, but you don’t know what it is, do you Mr. Jones?” In the opening first scene of the two-person play, coming2terms, at the Vineyard Playhouse, we’re all Mr. Joneses as we try to figure out what a particular attractive couple is up to. They’re coming across with everything long-term couples tend to do. Bickering? Check! Avoiding larger issues? Check! Sharing their day? Check!

The young man, Jeremy (Todd Gearhart) has just endured an ordeal that will live in infamy in his own personal bio: He placed his mad mother in a psych ward where she kicked, bit and screamed enough to do a werewolf proud. He and his sister are dealing with it, and now the young woman who stands before him, Sara (Kelly McAndrew), is appropriately caring.

But there’s other stuff going on within these four walls which, by the way, is a hotel room in the city. Why are they here, this pair who appears so conjoined, we figure they might as well be at home? Sara has brought over a paper sack of goodies out of which she draws a single martini glass. Okay, but where’s the other martini glass, not to mention the Bombay gin? Jeremy too requires more information for which he receives a long clinical discourse about a wide spout for receiving and a deeper funnel for consolidating proteins and enzymes, or something to that effect.

Sara and Jeremy have been best friends since the first grade. There is probably no one that the other loves more. In fact, Jeremy’s adoration for Sara is so complete that, should she become his in all the ways it is possible to be so, young Romeo Montague by comparison might wonder why he and Juliet can’t take it to the next level.

The situation is that Sara is a lesbian. She’s in a loving relationship with another woman, a banker (Sara is a Web site designer, Jeremy a startup entrepreneur), and Sara and her lover wish to have a baby. Sara also wishes for her oldest friend, Jeremy, to supply the sperm, and to preside as a daddy in the child’s life. Hence the hotel room and the martini glass: a more personal touch for an activity normally conducted in a doctor’s office with a plastic cup. (We’re spared the sight of the syringe or “dibble” into which the contents are transferred.)

During the course of the play, the two meet in a total of four trysts with the martini glass, two in a hotel room and two in Jeremy’s country house. The outside world, as it inevitably does, follows them inside. For Jeremy, this participation in what he calls “this science experiment” is exacerbated by his mother’s tormenting spiral into dementia and death. This in turn feeds into a normal, sensitive, prenatal quandary about bringing another human life into this world. This is not a trivial concern nor a casual hypothetical: After particularly grim times in history, humanity has been wont to ask if there is fairness and decency in making new babies to face potential fresh genocides, tsunamis, radioactive fallout, and four-hour SAT tests.

But Jeremy’s pessimism flows most predictably from the sheer perversity – from his point of view – of making a baby, with the girl he’s always loved, through the delivery system of a martini glass and a dibble. He is, if anything, maddened by the extent to which same-sex romance has ruined his life, or is ruining it for the time being.

In the course of the four trysts, life intervenes for both of them. No more of the plot shall be given away except to reveal that it’s all surprising and delicious. The dialogue is alternately sparkling and insightful, and often both simultaneously. Playwright and director Bill C. Davis wrote Mass Appeal, which began at the Manhattan Theatre Club and wound its way to a movie with Jack Lemmon and Charles Durning. He has continued to write, direct and act in plays on and off Broadway.

Todd Gearhart has appeared in major theatre venues, as well as in TV and movies. His Jeremy is handsome, funny, smart – all the traits that modern women look for in a guy, all except for the woman with whom he’s in love — not that she’s not mad about him platonically. At one point they acknowledge that they know so many of each other’s secrets, they’re saved from betrayal by Mutually Assured Destruction.

Kelly McAndrew has a roster of theatre credits, with a heavy immersion in Shakespeare, from playhouses all over the country. She’s appeared in TV series and movies, including Everybody’s Fine with Robert DeNiro. Her Sara is slim, blond, beautiful and witty; we can’t blame Jeremy for desiring her, but she’s completely grounded in her partnership of choice.

Chelsea McCarthy on costume design lent all the right touches to the wardrobes of two young cosmopolite professionals, neither of them edgy or trendy, only reassuringly comfortable in their own clothes as much as they are in their own skin. Each new scene begins with the actors on opposite sides of the stage talking to each other by phone as they shove arms and legs into whatever outfit they’re donning for the occasion.

Mac Young designed the flexible set suggestive of the kind of 1950s moderne that’s trendy in some New York hotels. Floors are black with salmon-rose and tan-colored scattered squares. Furniture is Danish or some equivalent thereof and, between scenes, with a fluid moving of bed, a table and a couple of chairs, we’re transported from hotel room to Jeremy’s house without a moment’s confusion. Master carpenter Christopher Kann collaborated with Mr. Young on the sets.

Fred J. Hancock spikes the lighting design with an intriguing turquoise pattern that comes and goes against the back wall. Kate Hancock serves as stage manager, Paul Munafo as sound designer, with Clark Maffitt on the sound board. As ever, Jim Novack lends his consigliere role to all aspects of sound production.

MJ Bruder Munafo, producer and artistic director of the playhouse, deserves continued kudos for another fresh choice of material.

Coming2terms, the second presentation of the 2011 summer season, will be playing through July 9; Tuesdays and Wednesdays at 7 p.m., Thursdays through Saturdays at 8 p.m. Tickets may be purchased online at vineyardplayhouse.org.