Megan Hilty is used to performing in large, star-studded casts on Broadway and television. She dazzled as Glinda the Good Witch in Wicked, rocked it as Doralee Rhodes in 9 to 5: the Musical, shined as Brooke Ashton in Noises Off and starred as Ivy Lynn in SMASH. She was nominated for a Tony Award for her performance in the farce Noises Off.

But on Saturday, July 16, at 8 p.m. she leaves behind the ensembles, elaborate costumes and television magic to be vulnerably herself onstage. She will perform on the Vineyard with Seth Rudetsky at the Performing Arts Center as a part of the inaugural Broadway at the Performing Arts Center concert series. The series benefits the Tyler Clementi Foundation, which promotes safe and inclusive spaces for LGBT youth and families.

In an effort to allow actors to be themselves on stage, Mr. Rudetsky designed a show that strips away any rehearsed varnish. Though Ms. Hilty has been joining Mr. Rudetsky in this style of show for several years now, she said every time they perform something new is created.

“It’s a really unique format, I love doing these shows with Seth Rudetsky, nobody really does it,” she told the Gazette in a recent phone interview. “It’s a cool way to know the artist on an intimate level. It’s not rehearsed or anything, the banter can’t be planned.”

She arrives at the theatre with about 16 songs prepared. She is ready to sing American standards, songs from Broadway, songs that everyone knows and loves, she said. But only seven to eight songs will be included in the show, and she has no idea which ones.

“A lot of one-person shows can get stale, this keeps it really honest,” she said.

The show begins as an interview, with Mr. Rudetsky asking her questions and guiding her to relive stories she may not of thought of sharing before. As she answers questions, Mr. Rudetsky decides which song she will sing and when. As the pianist and host, he is in control of the direction of the show.

“I don’t really choose,” Ms. Hilty confirmed. “He gets up and says ‘speaking of that, we’re going to sing this.’ I’m absolutely on my toes.”

For someone used to doing rehearsed, well-known musicals, this style of show is a refreshing change. It also shifts Ms. Hilty’s relationship with the song she said. Intertwining big Broadway hits with an intimate conversation can turn the songs on their head, and Ms. Hilty will sing a song she’s sung hundreds of times in a completely new way.

“He’ll ask me a question and get me remembering stories I haven’t thought about for years,” she said. “You are in a different emotional space and a different head space.”

Ms. Hilty had originally planned to clear her head with a week’s vacation on the Vineyard with her family. But then she was cast in TV Land’s pilot of a First Wives Club remake and had to change her plans to accommodate shooting the show. She said she will return to the Vineyard later in the summer for her vacation, but for now her one-night performance at the PAC will have to serve as her escape from the everyday.

“It’s one of my favorite things to do, it’s a chance to be myself for once,” she said.

For a full list of summer performers visit vineyardbroadway.com.