I've never met Ginni Harden Pierce, yet I feel that I know, almost intimately, a dozen different people she has inhabited in utterly believable performances. A gifted creator of character, she has appeared on local stages for more than 40 years, bringing to life a wide range of personalities, never more vividly than in the heartbreaking one-woman show, Joan Didion's "The Year of Magical Thinking," now at Blackfriars Theatre.

"You sit down to dinner," Didion writes, "and life as you know it ends." The randomness and inescapability of death haunt the book she wrote in 2004, the year after her husband, writer John Gregory Dunne, died of a heart attack. In 2006, she adapted it into a play, which she expanded to include the death of her daughter, Quintana, in 2005. When her father died, Quintana was unconscious from septic shock, the first of several dire illnesses, which led to her death at age 32. The play's timeline reaches from just before Dunne's heart attack to just after Quintana's death, but it remains elusive because talk is distracted by whatever associations and images roil the mind. The connections are deeper than logic.

The play is written as a one-sided conversation between a character named Joan Didion and an audience. In Pierce's modulated, restrained portrayal, Didion is talking and also listening to herself talk. She comments, analyzes, revisits, and revises because she prizes herself for being a rational person. Yet all that breaks down under the denial of death that she entitles, ironically, the year of magical thinking. If you believe something strongly enough - magically enough - you can keep it from happening, even if it is inevitable. So Didion refuses to give away her husband's shoes because he will need them when he returns. Didion's greatest need is to avoid what she calls the "vortex." She tries to do so by falling back on her ability to organize everything. She makes lists, she tells her friends again and again that she's "fine," she tracks down hospital reports - and she insists on being present for her husband's autopsy. She lets herself be talked out of it at the last minute.

Both Didion's writing and Pierce's speaking strike a perfect conversational pitch. Pierce's tone is straightforward; she treats us as if we will understand. Occasionally her voice hardens and a few times she pauses at the edge of tears, but only once does her voice rise in anger. The surprise of it cracks like a whip. For almost two hours, Pierce's voice is a revelatory instrument. She is aware that we are listening. It's as if she, as Didion, is the author of her own script.

Pierce also carries her script onstage with her. In a one-person play, the actor never gets to hide or even breathe. It hardly matters; you can do the job or you can't. She has the character, the language, and the rhythm of the talk, but on opening night she did not have all the words. From time to time she stumbled or paused to find the next sentence, sometimes she read a passage, but the momentary lapse never destroyed character or atmosphere because her grasp was so sure.

Just as Pierce conflates herself into Didion, so it's hard to know where Pierce ends and director Barbara Biddy begins. It feels not quite like an actor taking direction, but a different kind of conversation in which both are attuned to the play and one another, an essential but hidden part of the undertaking.

John Haldoupis' set is appropriately simple. Quiet blues and greens on a three-level stage; two Adirondack chairs as much to hold us in place as to sit in, along with a small table and a bench; and some tall panels with stars blinking randomly behind them while the perfect sphere of the earth floats above everything else.

Didion lives in a world of sophisticated affluence located on Manhattan's Upper East Side and in Beverly Hills, with Prada bags, manicures at poolside, and private jets to take a perilously ill daughter from one coast to the other. People die because they do, not because they lack for care. Much more suggestively, two lines echo through the play:

"You're safe," a mother tells her daughter. "I'm here now," though she will learn that, as hard as you try, it's never really true.

Parents and daughter tell one another, "I love you more than even one more day." It may be put to the test before it should have, but it articulates the sweet reassurance that roots the sorrow, the resistance, and the grief that begins before you recognize it.

"The Year of Magical Thinking"

Through January 29

Blackfriars Theatre, 795 E. Main St.

$27 | 454-1260, bftix.com