Fort Worth Opera director Darren K. Woods was looking for a Fort Worth story to mark the company's 70th anniversary. Someone mentioned that they thought President Kennedy spent his last night in the city.

"And I went, 'Everybody would know that if that happened,'" he says. "So we Googled it and boy: There it was."

The opera that resulted is named JFK, and its world premiere is tonight in Fort Worth, Texas. It tells the story of President John F. Kennedy's last night with his wife, Jacqueline, before he was assassinated on Nov. 22, 1963. But the opera is not what you might expect: It mixes intimate views of the couple's optimistic trip to Texas with dark hints of what we know will happen.

Woods asked librettist Royce Vavrek if he'd be interested in working on the project. Vavrek remembers his excitement at the idea.

"I remember running home and telling David that this was something I thought we could do are really, really well," Vavrek says.

"David" is composer David T. Little. He and Vavrek are based in New York. Both are in their 30s, and are rising stars in the opera scene. Their post-apocalyptic opera Dog Days landed on a number of critics' top 10 lists in 2012.

For inspiration for their latest collaboration, Vavrek and Little retraced Kennedy's steps in Fort Worth.

"I remember coming to this room, looking out these magnificent tall windows," Vavrek says, describing the presidential suite of what was the Hotel Texas, now the Fort Worth Hilton.

When the audience first sees Jackie in JFK, she's staring out that window, while the president soaks his notoriously bad back in the tub. Jackie injects him with morphine to numb the pain; he sleeps, and a series of drug-induced dreams and hallucinations follow. He meets his future wife for the first time.

Baritone Matthew Worth sings President Kennedy. He says he was enamored of the opera from the beginning. "The first day we sang it in workshop, we looked over at Royce and at David and said, 'Guys, this is just stunning,'" Worth says. "It still stays that way all this time later."

The original hotel suite where the Kennedys stayed that night was decorated with valuable artworks loaned by Fort Worth collectors. The painting Swimming, by Thomas Eakins, now hangs in the city's Amon Carter Museum of American Art. Little says it gave him some ideas.

"There was a kind of free association for us that started with these paintings, as the things that were surrounding the Kennedys in their suite," Little says. "You know: Would this remind Jack of Hyannisport? And sort of extrapolating from that — the Sea of Serenity on the moon, which is such a part of his presidency. In a way, they were part of a brainstorming process that helped us to construct us the broader frame for the story we were going to tell." Hyannisport and the moon both end up in this opera.

Throughout the show, there is a chorus: three Greek fates, Vavrek explains. They determine birth, life and death. The librettist says ancient myths have long been elements of grand opera, but here, he flips the convention.

"We took the myth of JFK and we really attempted to make him mortal," Vavrek says. "What were those conversations that he had with Jackie in the privacy of this suite? What are those, just, intimate things that we all deal with, that we could make him not a legend — we could make him a real personable figure."

They can only guess at what those conversations were. But Little says the team that produced JFK wants the audience to feel that tension between joy and impending tragedy.

"It's really about this affirmation of life," Little says, "because we know of the death that is imminent."

That's why President Kennedy sings of the sun shining the morning in Fort Worth before he and his wife leave. Sunny enough, he sings, to the leave the car top down.

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