To hear Jay O'Callahan tell it, a story's a thing alive. He doesn't just tell a story, he becomes it, body and soul.

You can witness the transformation at the Round House Theater in Silver Spring, where he's just settled in for a four-week run. He works magic, this gaunt, bearded chap who can turn himself into a teenage girl.

O'Callahan also works alone, without costumes, props or fancy lighting, often without makeup, and on a nearly bare stage. At rehearsal the other day, from a platform of plain pine, he spun out a yarn called The Herring Shed for a group of lucky intruders.

The story -- like much of O'Callahan's repertoire, his own creation -- concerns Maggie, a lass in Nova Scotia during the Second World War. To help in the war effort, and also to make some money, she spends her days impaling fish on rods inside an ice-cold shed. Over a single season she comes to grips with hard labor and bitter grief -- her brother dies in combat, along with two sons of a co-worker -- and so, very quickly, she comes of age.

Those are but the barest bones of the tale, which unfolds with the richness of a Russian novel. O'Callahan uses words, of course, but also song, dance, gesture, silence and some undefinable wizardry that can make his audience see and smell a wheat field and feel the chill of a herring shed.

This all would seem a parlor trick if it didn't seem so natural. He had me so in his power I neglected to take a single note.

O'Callahan, a 43-year-old New Englander, is one of a handful of professional storytellers -- artists who use everything from music to mime to make their work come alive.

"It's very close to music," he said during a break. "When you tell a story, as when you're conducting an orchestra, you're always creating and you're always surprised."

JAY O'CALLAHAN -- At the Round House Theater, 12210 Bushey Drive in Silver Spring, through August 8. 468-4234.