It's not the ending that actor Reese Britts envisioned for the biggest show of his career.

The star of Theater Latté Da's celebrated production of "Jelly's Last Jam" told friends Tuesday on Facebook that he had contracted COVID-19 and was "extremely heartbroken" he won't be finishing the last five performances of the musical at Minneapolis' Ritz Theater this weekend.

His understudy, Time Brickey, will be stepping into the title role of jazz icon Jelly Roll Morton.

"Understudies are truly the unsung heroes of the moment," Britts said. "They save our shows and the industry."

As COVID cases rise again, Twin Cities performing arts companies continue to test actors rigorously and maintain strict safety protocols. Mask mandates have been retained by some theaters, like the Guthrie and Children's Theatre, even as they have relaxed vaccination requirements. And, when necessary, they're tapping standby actors.

Understudies, in turn, are getting chances to shine. Brickey, who was already in the cast of "Jelly's" as Featured Dancer, says he's ready for his big moment.

"I'm mostly shocked that I'm going on," Brickey said Tuesday after getting a wardrobe fitting and looking over his script. "I was really enjoying doing my own track, and I'm a huge fan of Reese's performance. But I know the show back and forth, have done the work and am prepared."

Including shows at the Guthrie and Latté Da, scores of understudies are covering roles in shows such as "Footloose" at Chanhassen Dinner Theatres, "Diary of a Wimpy Kid the Musical" at Children's Theatre and "Memphis" at Artistry. Understudies used to be considered extraneous in the Twin Cities and actors didn't expect to go on partly because of industry mores. The prevailing show-must-go-on ethos of the theater world meant basically that only death should keep an actor from meeting their obligations.

So they sacrificed their health, relationships, holidays, weddings and other important milestones. COVID-19, and new demands by artists, have made the performing arts world take sober stock.

Brickey is part of a dynamic understudy duo. He sometimes runs lines with his sister, China Brickey, an actor who also is understudying at the moment. China Brickey covers the roles of daughter Beneatha and daughter-in-law Ruth in the Guthrie Theater's acclaimed production of "A Raisin in the Sun." She went on during previews in one of them.

"It's a wild time to be an understudy," China Brickey said.

Her contract started just before previews, and "15 minutes before I was to show up and start taking notes, it was, 'By the way, maybe you can go on for first preview?' It's a crazy job."

Her background prepared her to be flexible and dynamic.

"I moved to Minnesota [from Chicago] to be an apprentice at [the Children's Theatre Company], and half of your job there is understudying everything," Brickey said. "I learned quickly that I would go on so I did a lot of understudy training and still swear by my little yellow book, 'Be the Best Swing on Broadway.'"

Twin Cities theaters also have met the challenge.

"There's been a great call from the field for us to adjust our practices to make the workplace more humane," said Guthrie Theater artistic director Joseph Haj, a former actor. "Work has changed fundamentally for us. The field has adopted a healthier philosophy."

The Guthrie has eliminated the grueling technical rehearsals that had actors called in at noon and released at midnight. Other companies across the country have as well.

The upshot is that, like everywhere else, the increase in uncertainty has meant an increase in costs, and not just for health care. Theaters, which buy plywood in bulk for set building, pay significantly more now to fulfill their mission.

Still, putting on plays is what they're called to do, even if they have to take many more steps to do so safely. After two student matinees of "Wimpy Kid" were canceled last week because of a COVID case at the Children's Theatre, artistic director Peter Brosius counted his blessings.

The losses may have been greater if not for understudies.

"They make the world go 'round," Brosius said. "It's been such a wild time in the American theater, but we want to make sure that our actors are taken care of and our audience can see the shows."