NEW YORK - Broadway is the last place Priscilla Smith Herreid expected to report for work while on leave from the Philadelphia Renaissance wind band Piffaro. Nor did she train for a career in music at Temple University and the Juilliard School in order to work with a great Shakespearean actor like Mark Rylance.

Yet here she is at the Belasco, where Shakespeare's Globe Theatre is performing Richard III, along with Twelfth Night, eight times a week to rave reviews. She plays a Renaissance-era shawm - precursor of today's oboe - to underscore each and every beheading.

How does she play differently for other unspeakable acts? "Louder," she says, "and more articulate. We just try to hit you more over the head.

"With Piffaro, we play . . . soft and with a good shaping of the lines. You still want lines and shapes here, but to a different purpose, to say, 'Here's the king, and he's going to kill you.' "

Near the end, she trades her shawm for bagpipes, creating a pastoral counterpart to Rylance's Richard, who is having a sword shoved down his armor. "Here you're with the most amazing actor to date, he's been killed off, and I'm hoping my bagpipe doesn't make any rude noises that distract from the intensity of the scene - which it can," she said, backstage on a two-performance day.

Having been hired in October as a wind player, she caused much delight when she offered to replace a departing bagpiper as well, since the show has been extended to Feb. 16. More-seasoned theater musicians say a four-month run is the perfect length; longer and a show may start to feel tiresome.

But Herreid, 27, who has been promoted to Richard III music director, would happily go for another four months, especially since her husband, fellow Piffaro member Grant Herreid, is about to join the company as a lutenist.

The musicians are indeed part of the company, she says.

"Everybody shares a dressing room. Nobody is held up high. Mark knows everybody's name, even the ushers. He says, 'You OK up there? Do you have everything you need?' And I think, 'You're Mark Rylance! Somebody else will take care of us.' You want to do your job so that he doesn't ever worry about us."

The Globe's mandate has been to re-create Elizabethan performance practices as closely as is viable. Past productions have scattered rushes - grasslike stems - over the stage to muffle footfall noise. Women's roles are played by young men. Though she's only intermittently visible in the gallery overlooking the stage, Herreid is in Elizabethan costume.

Such procedures are not unprecedented in Piffaro's world. During one of the group's appearances at the Utrecht Early Music Festival in the Netherlands, Herreid participated in a re-creation of the funeral service for Philip II of Spain, coffin and all. The experience was crowded, chilly, and uncomfortable, but it instilled in her a sense of audience responsibility that now serves her well: "Seeing 1,000 people [in Utrecht] leaning over in uncomfortable positions, I knew I had to give it my all."

The Globe productions are similarly demanding. The offstage areas where she plays are drafty and can cause the instruments to go out of tune. In a way, though, she almost welcomes discomfort. "I like living on the edge that way," she says.

One thing she learned from her parents - her father is the noted composer Kile Smith - is that you can whine at home, but not on the job. You show up on time, prepared, and with a good attitude, particularly in the freelance world where there's little job security.

"When I was 12, I wanted to be a freelancer because my parents' friends were, and they were cool. I like the way they went from job to job," she says. "I like . . . not doing the same thing every day."

That's not likely to happen, given all the instruments she plays. She grew up playing recorder, but in her preteen years picked up a modern oboe and a few months later was drafted by the Olney Symphony Orchestra to play the famous oboe solo in Beethoven's Symphony No. 6. She was perfect on her first attempt, says music director Jack Moore.

Though she studied oboe at Temple University, she had closely studied Piffaro's recordings and began performing with the group, whose members are required to play as wide a range of instruments as possible. When her father was commissioned to write what became his breakthrough piece, Vespers, for Piffaro and the Crossing choir, he consulted his daughter on the use of shawms.

"Everything Priscilla does astonishes me," he said. "She has this great musical fearlessness, which is a combination of complete musicianship, technique, and a sense of adventure."

That's one reason that - shortly after arriving in New York five years ago to study at Juilliard - she quickly became an in-demand freelancer, so much so that her parents, who are heavily involved in music at their church, joked that the only way they could see their daughter was by hiring her.

It's possible that her trump card is passion. Musicians with an incidental role in the theater aren't necessarily required to have any great emotional involvement. But Herreid couldn't have resisted the actors if she tried.

"I think, 'Oh, that's so beautiful. And now I have top it,' " she says.

During her current gig, Herreid has yet to see the famous Belasco Theatre ghost - though there have been some tough-to-explain occurrences. The stage is partly illuminated by natural candlelight, and during one recent performance, an entire set of candles burned down so quickly they didn't last to the end of the play.

"What draft," she asks, "is making those candles melt so fast?"