Like the best ghost stories, "The Turn of the Screw" draws its power not from oversize effects, but from the intimacy and taunting plainness of its approach. That's true of Henry James' novella, and just as true of the intricate and beautiful chamber opera that Benjamin Britten created from it in 1954.
Intimacy and precision are the hallmarks of San Francisco Lyric Opera's splendid production of the opera, now playing at the Cowell Theatre in Fort Mason. Conducted with exemplary care by Artistic Director Barnaby Palmer and sung by a uniformly fine cast, Sunday's matinee performance allowed the audience to witness the work's magic right up close, without flinching or cheating.
That transparency is part of the challenge in this swift, crystalline masterpiece. Scored for just 13 instruments and a small cast - at least one of whom is a child - "The Turn of the Screw" is a fully exposed venture that leaves performers nowhere to hide.
Instead, the shadows and secret corners are in the story itself. As in James' original text, it concerns an unnamed governess who takes a job at a remote country house tending to two seemingly angelic, but mysterious, children.
Her assignment turns out to involve grappling with two malevolent specters for possession of her young charges - a struggle in which the children's allegiances are unclear. For that matter, the very existence of the two ghosts is a matter of speculation.
Britten and his librettist, Myfanwy Piper, necessarily bring things into somewhat crisper focus for the stage. They give the ghosts - the former valet, Peter Quint, and the former governess, Miss Jessel - music to sing, and they make far more explicit the subtext of sexual predation, including a portentous quotation from Yeats ("The ceremony of innocence is drowned!").
Still, the elusive quality of the original lives on in the evasions and ambiguities of the libretto, and especially in the haunting flourishes and mood changes of Britten's score.
Britten understood that the spookiest effects come from the presence of the otherworldly within the everyday. So his score is laden with images of childhood innocence - nursery rhymes, schoolroom mnemonics and the practicing of early piano lessons - alongside the eerie vocal swoops of the phantoms and the ghostly tinkling of the celesta.
Among the opera's difficulties, perhaps none is so daunting as the composer's expectations from his two child stars (although in other productions the role of Flora, the younger child, is sometimes taken by a woman). The Lyric's production is blessed with not one but two young artists who rise magnificently to the challenge.
Brooks Fisher, who plays Miles, boasts a clear, sumptuous treble whose pure tones don't interfere with either audibility or clarity of diction. He captured Miles' unnerving combination of innocence and darkness in a performance that always seemed, tantalizingly, to be holding something back.
He was well matched by Madelaine Matej as Flora, her singing bright and true, and her stage presence a compelling mixture of playfulness and turmoil.
The rest of the cast was no less fine. Soprano Anja Strauss brought vivid vocalism and a keen sense of anguish to the part of the Governess, and Kathleen Moss was a warm-toned, vivacious presence as the housekeeper, Mrs. Grose.
Tenor Trey Costerisan, doubling as Quint and the Prologue who narrates the premise of the story, gave a sensational performance marked by fluid phrasing, lustrous tone and uncanny accuracy. Soprano Lara Bruckmann's Miss Jessel was aptly dark and menacing.
Palmer led a crackerjack instrumental ensemble with assurance, if a bit too fastidiously. Director Heather Carolo's staging, helped along by the video projections of scenic designer Jean-François Revon, underscored the work's unknowable qualities.
Turn of the Screw: San Francisco Lyric Opera. By Benjamin Britten. 7:30 p.m. Fri.-Sat. Cowell Theatre, Fort Mason. Tickets: $18-$32. Call (415) 345-7575 or go to www.sflyricopera.org.
Trey Costerisan, doubling as Peter Quint and the Prologue, was sensational with phrasing and a lustrous tone.