The silences in "Tribes" are so deafening they roar. Nina Raine's penetrating new play forces us to hear the world differently.

The critically acclaimed domestic drama revolves around a deaf young man reared by a chaotically verbal family. Sensitively directed by Jonathan Moscone, the play both explores how the deaf experience of the world and suggests that all language limits our ability to communicate shades of truth.

If the play never quite achieves the emotional crescendo it strives for, this family's heady patois of banter and bile is immensely pleasurable, a symphony in snarkiness. Todd Rosenthal's gorgeously cluttered set captures the intellectual nature of this clan. Teetering towers of books and bohemian knickknacks vie for the eye.

MELLOPIX.COM/BERKELEY REPERTORY THEATREBilly (played by James Caverly, left), who is deaf, shocks his family by announcing he will only speak to them in
MELLOPIX.COM/BERKELEY REPERTORY THEATRE Billy (played by James Caverly, left), who is deaf, shocks his family by announcing he will only speak to them in sign language, in "Tribes." The family includes his mother (Anita Carey), brother (Dan Clegg) and sister (Elizabeth Morton). ( alessandra mello )

Meet Christopher (a ferociously funny Paul Whitworth) the scabrously witty head of a British family for whom mockery and derision pass for intimacy. A scholar who tears into his wife Beth (Anita Carey) and children Ruth (Elizabeth Morton) and Daniel (an explosive turn by Dan Clegg) as if they were hastily-written term papers, Christopher never met a criticism he didn't like. Surviving his vicious sense of humor is a rite of passage for this troubled brood. In this house, bollocks is a term of endearment.

Steeped in a cauldron of negativity since childhood, Ruth battles timidity even as she pursues a life as an opera diva, while Daniel manifests his self-loathing by perpetually rewriting his thesis. Family dinner is a tidal wave of rage and bitterness cloaked in wit and literary allusions. Only deaf Billy (James Caverly, who is a deaf actor) sits above the fray, shielded by his oasis of quiet.

His uneasy truce with his warring family falls apart when he falls for a woman raised in a deaf family. Slyvia (Nell Geisslinger) is slowly losing her hearing, crossing a bridge into Billy's universe, and when she teaches him how to sign, it upends his life.

Geisslinger, an Oregon Shakespeare Festival vet, subtly captures the strain Sylvia is under, translating for everyone around her even as she loses her grip on her sense of self. She also conveys the complexity of sign language as a ballet that invokes the whole body.

Sylvia's meet-the-parents scene is the heart of the play. If the romantic connection between Caverly and Geisslinger never seems palpable enough to ground Billy's epiphany, the battles between Whitworth (best known as former head of Shakespeare Santa Cruz) and Geisslinger crackle with electricity. He belittles the subtleties of sign language while she defends her mother tongue. It's a scintillating debate, lit with insights into the hierarchies and rituals of the deaf community.

Unfortunately the second act doesn't build on this intriguing setup as well as it might. Raine sometimes telegraphs her themes too much while failing to flesh out the eccentricities of her characters. Slyvia's journey into deafness is far more interesting than the extravagant angst of Billy's siblings, which takes up a bit too much time (although Clegg is a riveting portrait in thwarted passion as the disturbed Daniel).

Billy, for instance, remains somewhat vague in terms of his personality. Without more of a sense of who Billy is, it's hard to care about his ethical quandaries.

This lack of specificity undermines the emotional intensity of the production, which doesn't quite earn its tearful final tableau.

Still it's quite stimulating to have to listen hard and look closely from start to finish. You can't make out everything Billy says and not all of the sign language is translated into subtitles. All of this stagecraft reminds us how interpretive words are, how elusive meaning can be. As a deconstruction of language, "Tribes" resonates loud and clear.

Contact Karen D'Souza at 408-271-3772. Read her at www.mercurynews.com/karen-dsouza, and follow her at Twitter.com/karendsouza4.

"TRIBES"

By Nina Raine, presented by Berkeley Repertory Theatre

Through: May 18
Where: Berkeley Rep Thrust Stage, 2025 Addison St., Berkeley
running time: 2 hours, one intermission
Tickets: $29-$99, 510-647-2949, www.berkeleyrep.org