The living room is a borderland, where playwright Octavio Solis is comfortable mixing flights of poetry and surreal behavior to tell his story of Lydia, which is grounded in a gritty realism. And if by the end of the latest Marin Theatre Company production it all becomes too much of a good thing, and the plot becomes a Mexican soap opera, audiences will still get their money's worth of thought-provoking entertainment in a setting that is as exotic for Marin audiences as a kabuki play.

Set in 1970 El Paso, the story is told through the voice of young Ceci (Gloria Garayua), who lies on a mattress downstage. She is speechless, except when she floats back to the past or when she listens to her Mexican-immigrant family disintegrating--as each deals with the guilt of the car crash that damaged her brain.

The accident happened on the eve of her quinceañera, the birthday that made her a woman and one that meant sex with her adored cousin, Alvaro (Elias Escobedo). She is frustrated and asks God how he could take away her brain but leave her horny. Her brother Rene (Lakin Valdez) spends his time fag-bashing GIs while denying his own love for Alvaro, who has run away to war rather than admit his love for Rene.

Young Misha (David Pintado) is the sensitive teen who will in time write the story, and who comes to sexual life when Lydia (Adriana Gaviria) arrives to take care of Ceci and ends up taking on the whole family--which includes the fiercely maternal Rosa (Wilma Bonet) and a father (Luis Saguar) who speaks with his fists.

Director Jasson Minadakis creates Solis' falling-apart family with spotlights on their public life and blue shadows on their inner. He doesn't neglect the frequent humor, as when the boys talk about the war in Vietnam and Misha vows he'll go to Canada. "You're already on the border," Rene says, "Canada is for the white boys."

Robert Mark Morgan creates a set with colorful and exotic accessories alongside Sears-style furniture. The ensemble is outstanding; each member has emotional and painfully beautiful moments dealing with Ceci. Saguar sings softly to her, revealing a soft side; Misha confesses private thoughts and even Rene is tender and loving. Lydia is a lovely girl-woman who changes everything and Gaviria keeps her as mysterious as the playwright intended.

Lydia is a play where plot gets in the way. One could spend a week just getting to know this family.

***
The Last Night of Ballyhoo is a production with a split a mile wide, one that playwright Alfred Uhry and director Phoebe Moyer haven't mended. It is a romp through lives of rich Jews in Atlanta as Boo Levy (Mary Ann Rodgers) tries to get her problem child, Lala (Lauren E. Becker), a date for the Ballyhoo dance.

Boo cajoles, pleads, nags and shouts as a Southern mother who would make Amanda Wingfield cringe over her glass menagerie. Lala responds with pouts and flounces, but when Peachy Weil (Kurt Gundersen) shows up, sweetness flows as each waits for him to pop the question. The red-headed Peachy is enamored of his foolishness; Gundersen plays this blundering boy big, and his scenes with Becker's giggling and silly Lala are fun. Like the mother/daughter scenes, they are played for farce.

Another story is going on with Boo's sister-in-law, Reba (Molly McGrath), and her Wellesley daughter, Sunny (Alicia Bruckman). And then there is Adolph (Alex Ross), who has taken care of all the women since his brother's death. Sunny is clearly his favorite, and he is fond of Reba, but tries to ignore Boo and Lala. He is delighted when Sunny and his new employee Joe (Mike Cernokus) hit it off. But Joe, who is a Polish Jew (one of "the other kind" according to these German Jews), sees that Sunny and her family are more interested in running with the WASP crowd than paying respect to their Jewish heritage, he bolts.

Both are good stories, and Moyer keeps the action and dialogue moving fast and her actors keep a fast pace. Rodgers and Becker play their conflicts like a tennis match with Ross as the likeable ball in play. McGrath pleases in a nuanced role that is overwhelmed by the energetic Boo. Bruckman and Cernokus's problems, while real, are not set up well, but their romantic courtship plays with charm. And Gundersen makes his stock character entertaining.

Playwright Uhry grew up among these people; his Driving Miss Daisy combined their comic aspirations and prejudices even as he created a deeply moving relationship between Miss Daisy and her longtime chauffeur, Hoke. The Last Night of Ballyhoo is fun to watch, and the actors gave us a good ride. But a play's ending should be surprising but inevitable, and this was merely surprising.

***
NOW PLAYING
Lydia runs through April 12 at Marin Theatre Company, 397 Miller Ave., Mill Valley; 415/388-5208, www.marintheatre.org.

The Last Night of Ballyhoo runs through April 26 at the Barn Theatre, Marin Art & Garden Center, 30 Sir Francis Drake Blvd., Ross; 415/456-9555, www.rossvalleyplayers.com.

Are you receiving Express, our free daily e-mail edition? See a sample and sign-up for Express.