In early March, the behind-the-scenes drama at the Los Angeles Opera’s opening night of The Flying Dutchman almost overwhelmed the plot twists of Wagner’s operatic love story.

Twenty minutes before the curtain was set to rise at the Dorothy Chandler Pavilion, an unofficial announcement circulated that Portuguese soprano Elisabete Matos, already in costume and makeup for her LA debut, was ailing from mild chest congestion.

By 7:18 p.m., Matos stepped down from her lead role of Senta, and USC Thornton School of Music alumna Julie Makerov replaced her — with 12 minutes to spare.

Makerov had previously performed the role of Senta in Salzburg, Austria, with the Mozarteum Orchestra and won the 2010 Dora Award in Canada for her performance with the Canadian Opera Company. She’d attended the rehearsals for the LA Opera production as a “cover,” the opera world’s term for unseen replacements waiting in the wings.

“It was a little disconcerting not to have done a walk-through, but I’m a professional. I’ve seen a couple of stages before,” Makerov said with characteristic good humor.

After earning her master’s degree at USC Thornton in 2000, Makerov sang as the resident artist at Opera San Jose and was a grand finalist at the Metropolitan Opera Competition. The concert at the Met brought her to the attention of a manager, and engagements followed in opera houses across the United States, Canada, Europe and Asia.

“Once I was in costume and makeup, I had the opportunity to walk the stage while the audience was filtering in,” Makerov said. “I practiced falling, and thank goodness it wasn’t a crazy costume. Once I got on stage, I thought, OK, this is fine.”

Makerov’s last-minute debut earned her a standing ovation, a great review in the Los Angeles Times and compliments from Tómas Tómasson, the Icelandic baritone who played opposite her in the title role. Tómasson told the newspaper about his own experience years before when he filled in as the Flying Dutchman on opening night of a performance in Barcelona.

Opera covers are the equivalent of an understudy in the theater. The roles are particularly prevalent in the United States due to geography. Unlike smaller European cities, where a replacement soprano or other singer is only a short drive away, many North American opera houses require covers as a regular aspect of every performance. Some, like the Met, go to the extreme of hiring a cover for every role in a production, no matter how small.

Opera buffs collect stories of covers who have launched successful careers after filling in for an ailing principal performer. Everyone seems to have a story about a late replacement.

“When I first began in the business, I was a production assistant in Santa Fe for The Marriage of Figaro,” said Ken Cazan, resident stage director of the USC Thornton Opera and chair of the Vocal Arts and Opera program. “One night, after the first act, the soprano singing the massive role of Susanna got sick. The conductor happened to be married to a young soprano who was sitting in the audience, had seen the dress rehearsals and had sung this particular English-language translation before.

“She was thrown into a costume, wig and makeup. I explained the staging for the next act and thrust her onstage much to the surprise of the countess, who had just sung her first, difficult aria, ‘Dove sono.’ I stood in the wings with a 10-pound production book shouting stage directions to the woman, and it was a great success.”

Tonight, Cazan will lead the USC Thornton Opera at Bing Theatre in a production of Poulenc’s Dialogues of the Carmelites. Cazan is renowned for taking risks and adding fresh perspectives to his work, and this new production is no different. The opera has been reimagined to take place during World War II and will feature video and projections of Nazi tanks entering France.

Like the dramatic endings of the operas he stages, Cazan’s story about the cover being pulled from the audience in Santa Fe had an unexpected twist: “Three years later, I was hired to direct a production in Santa Fe of Le Nozze di Figaro, this time in Italian,” Cazan said. “I was thrilled to see that the woman cast as Susanna was the same one who had lept from audience to stage at the Santa Fe Opera!”

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