When he stands upon a setless stage Saturday night, Jay O'Callahan's only costume will be a vest. He'll use almost no props. But his audience will see more than a bearded, lanky middle-aged New England storyteller gesticulating broadly.

They'll see an old-maid store clerk whose "elbows bruise the air" as she marches into town, and a youth with a "smile like a crack in an apple" taking on adult concerns, trying to keep his family farm together in Depression-era Ohio. They'll see a lantern swinging over a river and perhaps even feel a dry leaf as it brushes against a cheek.

O'Callahan, described by Time magazine as "a genius among storytellers" and a "theater troupe inside one body," has been a prominent leader among those creating and discovering a new interest in storytelling as an art form. He began by creating stories for young audiences 10 years ago. Now, with increasing demands for adult performances, telling stories to children fills only a third of his schedule.

Recently the Boston Symphony commissioned O'Callahan to write and perform the stories that inspired Zoltan Koda'ly to write his "Ha'ry Ja'nos." Commissioned by the town of Harvard, Mass., to create a performance to celebrate its 250th anniversary, he interviewed old-timers, learned of Harvard residents in the 1920s and '30s and worked those experiences into a segment of a program called "Village Heroes," which was held over in Boston for 10 weeks.

Because of his theater and literary talents, O'Callahan has melded the tales and the telling with acting. He uses song, rhythm, gesture -- whatever he can -- to bring his characters to life and their surroundings into the imaginations of his listeners. Without abdicating the "telling," he simultaneously "becomes" the characters. "Jay O'Callahan has got to let go," he says. "If it's half Jay O'Callahan and half character, it doesn't work." The same is true, he says, "if there's stiffening up or lack of total commitment."

O'Callahan's key to total commitment has been to write his own material. A storytelling tour in Africa persuaded him that people respond best to tales that move the teller. In Niger and Mauritius he performed both his own and African folk tales. "When I told my own stories, that's when things came alive," he says, even though they dealt with culturally different settings and unfamiliar customs. "They were responding to something universal," he says.

O'Callahan has found the increased interest a spur to his creativity. "I'm using a form which is to me more immediate than print or records," he says. "It's me and my voice and the audience. Somehow all of us, through the sound and the rhythms, suddenly enter into a character's world, and they say, 'All right, we make this man a young girl, an old soldier.' "

In a long story called "Raspberries," a child-oriented performance, he portrays an array of characters, rapidly "becoming" each one as the story and dialogue unfold. As a young baker he works with rhythmic joy singing "Kneadin', kneadin', all I do is kneadin'."

To create spunky, sprightly, 92-year old Mrs. Stevenson about to taste an astonishing raspberry tart that causes the taster to jump into the air and shout, he bends way over. "Mrs. Stevenson took a bite of the tart," he says, pausing, with caution in his voice, "and flew into the air!" His body goes straight up. "Raaaaaaaspberries!" he shrieks. After a school performance, O'Callahan says, he heard a boy ask a classmate, "Did you see that old lady jump?"

A major portion of "Village Heroes" concerns a week in the life of Edna Robinson, a lonely Harvard spinster who experiences a moment of courage and learns to love living. "The story still moves me enormously," O'Callahan says. "Every night I look forward to doing that story."

Jay O'Callahan will perform "Village Heroes" Saturday at 8:30 p.m. at the Department of Commerce's Hoover Auditorium, 14th Street and Pennsylvania Avenue NW.