When the Off-Broadway smash musical/movie spoof “Titaníque” set sail on its maiden voyage on the Great White Way on Apr. 12 (with “Big Bang Theory” star Jim Parsons at the helm), NYC actor and songwriter Tess Marshall made her Broadway debut — but you didn’t see her on stage.
Instead, the 31-year-old first-time understudy — whose contract as an offstage “swing” covers the five action-packed roles of Celine Dion, Rose, Molly Brown and more — watched from the house of the St. James Theatre with her fellow players-in-waiting, cheering on the principal cast and waiting in case she was summoned.
As the run continues through mid-July, Marshall, who also works as the show’s dance captain, remains backstage at every show prepared to jump in for a sick, injured or otherwise indisposed colleague at a moment’s notice — something that might strike heart-pounding panic in most, but it’s all in a day’s work for Marshall.
Marshall is just one of the hardworking understudies, swings and standbys playing in the 40+ Broadway shows for the 2025-2026 season. Understudies typically double as ensemble members who perform nightly while covering lead/supporting roles; swings are offstage performers covering various ensemble tracks; and standbys serve as offstage covers dedicated to one lead role.
Wearing many hats on Broadway isn’t even the half of it for Marshall. Although she also works as a voice teacher — not for the money but because she loves it — performs as the lead singer of a rock band, is releasing her first solo album this summer, and occasionally acts in TV, video game and commercial gigs.
But when the call comes, she drops it all and goes — with little to no rehearsal time — a common practice on NYC’s many stages.
“The ability of swings to adjust by ‘trial by fire’ is incredible,’ Marshall told The Post. “You take in all the information you can while watching the principals rehearse the songs and dances — then sometimes you’re on. I know many swings who’ve gone on for a performance with no rehearsal at all.”
‘A total leap of faith’
Although she aspires to eventually become a principal Broadway actor, Marshall initially had doubts over whether she could even fulfill the complex, all-encompassing role of a swing.
“I remember sitting on jobs where I was the principal, looking at the swings and going, ‘I am in awe that these people can hold this much in their brains and that they could be potentially going on without proper rehearsal,’” Marshall admitted.
“So when I was offered the role of a swing in “Titanique” Off-Broadway and then on Broadway, I remember thinking, ‘I can’t do this.’ Saying yes was a total leap of faith. I turned out to be really good at it,” she continued.
It’s a role she’s glad she took, even if it means remaining in a constant state of readiness, which for her means daily warmups for each role, sleeping with a humidifier to keep her voice healthy and a “regimented” strength and cardio routine that she partakes in on show days.
That isn’t to say Marshall hasn’t gotten sick when needing to jump into character, as she’s performed in the Off-Broadway version of “Titaníque” “under every (physical) condition you can possibly imagine” — including post-laryngitis and while actively suffering from Norovirus, one time even throwing up mid-show (backstage, thankfully).
Another challenging part of the job is that she’s required to be in the building for every single performance and has, in the past, gone onstage with as little as 10 minutes’ notice before the production — or even mid-show.
“I’ve been in my dressing room and gotten a ‘Knock-knock, you’re on!’,” she said. “Somebody’s late, or the train got stuck, or they’re having an emergency. Things happen. The nature of being a swing is that you never know how much notice you’re going to have, and my job is to be able to go on…”
“…The likelihood that someone will go on without any rehearsal is very high,” Marshall explained. “It’s really important to have a process that works for you, since you might be sticking a tracking sheet on your body somewhere and going on stage for a paying audience.”
‘A lot of cardio’
Vance Klassen, the 26-year-old actor who currently understudies the lead role of Elder Price (currently played by Kevin Clay) in “The Book of Mormon” on Broadway while regularly a part of the ensemble cast, has been covering this role since August of 2022, when he began his time with the show’s national tour.
“For me, this feels like it’s been about a decade in the making,” Klassen told The Post. “I remember hearing the original cast (album) when I was in high school and my mom saw the tour, and her saying she could see me doing that one day as well.”
“When you have a dream, sort of coming to a point at that one moment, it’s a little surreal.”
For Klassen, pursuing that dream also involves working as an administrative assistant and licensed salesperson for a real estate brokerage in midtown Manhattan during the day to make some extra cash.
On a typical workday, he can be found answering emails, showing apartments, auditioning for other performances, logging a few hours of admin tasks — and then “walking over to the theater to tap dance on Broadway.”
This work ethic transfers to his workout routine. While the show itself is “a lot of cardio,” Klassen focuses his time at the gym (at least three days a week) on lifting weights and maintaining mobility to keep his strength and endurance up.
“I wore my fitness tracker during a rehearsal run and discovered that I burn just over 700 calories per show on average,” Klassen explained.
In addition, Klassen routinely does vocal check-ins as soon as he wakes up to make sure there aren’t any signs of “inflammation, soreness, mucus, all the obstacles keeping me from functioning at my best,” since, as he describes it, “our body is our instrument (and our source of income).”
‘I feel like a corpse’
Gerianne Pérez, the 35-year-old actor who understudies three principal roles in the Tony- and Olivier Award-winning musical comedy “Operation Mincemeat,” knows just how important it is to keep her body in tip-top shape.
“I work with a personal trainer,” Pérez told The Post. “I strength train about four times a week, aim for at least 12,000 steps a day and mix in light yoga to stay stretched and help prevent injury,” in addition to drinking 100+ ounces of water daily, eating an anti-inflammatory diet and doing monthly voice lessons to keep her voice “in tip-top shape.”
Having made her own Broadway debut in the a cappella musical “In Transit” in 2016 as both a featured actor and cover for one of the principal roles, Pérez then booked the national tour of Sara Bareilles’ musical “Waitress,” where she understudied the role of Dawn and did the same on Broadway.
Fast forward to late 2024, when she heard that “Operation Mincemeat” was coming from the West End to Broadway, she was initially hesitant to audition, unsure if the zany show was in her wheelhouse, but eventually “decided to take a leap and go in for it. I thought, ‘Why not try something that scares you?’”
Now, over a year after becoming part of the “OM” Broadway cast as an understudy and going on with the show over 85 times, Pérez has her workdays down pat, which does include some side hustles.
Although being a swing, understudy or standby is a full-time job in a unionized industry, like Marshall and Klassen, Pérez works multiple “survival jobs” such as audition coaching, teaching masterclasses, and content creation to keep up with the cost of living in NYC.
“For a role like mine, that base is around $2,700 a week, with additional pay depending on covers and additional responsibilities. And while that number can sound high, you also have to factor in things like agent commission, which is 10%,” she told The Post.
Pérez tries her best not to do anything that could potentially jeopardize her body or voice — like having a cocktail or getting bloodwork done — if she were called to fill in.
That said, she recalled, “Once, I was flying back from a family trip in Florida with the flu and got the call before boarding that I’d be on that night,” said Pérez.
“It turned into a pretty intense lung infection. I remember looking at myself in the mirror during hair and makeup thinking, ‘I cannot believe I’m about to do this — I feel like a corpse.’
“But we were down coverage, and that’s the job — you show up and make it work however you can.”
Even when Pérez isn’t called to play one of her three versatile tracks onstage, she still spends the majority of her nights at the John Golden Theatre in Midtown, where she does one of three things during the two-and-a-half hour performances: rehearses a particular track of the show in her 100-square feet shared dressing room; watches from the house with a notepad and pen; or shadows principals backstage (a common practice for understudies known as trailing) — constantly shifting her attention to “what the show needs from me.”
With so much to juggle, Pérez is no stranger to the occasional disappointment from audience members who had expected a different performer.
“I think people don’t always realize that understudies aren’t just ‘backup’ — we’re a really essential part of what keeps Broadway running,” said Pérez. “There’s a huge level of mental and physical athleticism involved. You’re holding multiple tracks in your body at once, and you have to be ready to jump in at any moment and lead a show.”
However, Pérez feels grateful for the way the majority of the “incredible fanbase” at “OM” have received her for planned understudy performances.
“For one of my track debuts, some of the fans made pins and T-shirts with my face on them. Easily 30 plus people bought tickets to see that debut. It was one of the most rewarding nights of my career.”