By Cindy Hsu

NEW YORK (CBSNewYork) – It takes a team to put on a Broadway show, and ensemble members play a key role – especially when they step into the lead, and the spotlight.

Those performers may not have their names on the marquee, but they make sure shows don’t miss a beat.

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CBS2’s Cindy Hsu sat in on a rehearsal for “Girl From The North County.”

When you see a Broadway show, the principal or lead actors get most of the attention, but there’s a whole team of understudies, swings and ensemble members that complete the cast.

“I understudy three characters in addition to the role I play each night in the ensemble. So it’s a lot,” said actor Chelsea Lee Williams.

Williams is a perfect example of how multi-talented the actors must be. A “swing” is a performer who can often play many roles, but is not in every performance. An ensemble member is a supporting actor who is on stage for every show.

“A musical is built by those people who are going to keep that show on every night, eight shows a week. And so the ensemble, it’s crucial,” said Broadway producer Tristan Baker.

CBS2 went behind the scenes of the Bob Dylan Musical “Girl From The North Country” to watch the understudies rehearse.

“You have to know all the choreography, all the lines, you know, all the details, so that you are prepared to go on at a moment’s notice,” Williams said.

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An understudy can even be called on to cover a role in the middle of a show.

“People get sick, or there’s traffic, or the subway is shut down and the train is late,” Williams said.

In addition to two rehearsals every week, Williams says she has a ritual during her train ride to work to help remember all the lines for so many different characters.

“From my commute from Brooklyn to here, I go over all my lines make sure they are pretty much second nature. I don’t have to think about them. I don’t have to look for them. They’re just in my memory,” Williams said.

So what’s it like when she gets that call to fill in?

“Your heart skips a beat a little bit, but then you’re like ‘I don’t have time to be nervous,'” she said.

Williams says it’s an incredible job that takes nerves of steel.

“You have to be fearless, and you have to be ready for anything,” she said.

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“Girl From the North Country” is playing at the Belasco Theatre and closes on January 23rd, but they hope to be back in the spring.

Cindy Hsu