By Randi Bjornstad

Siri Vik’s big show at The Shedd this week, the famous The Seven Deadly Sins “sung ballet” — which was the last major collaboration between writer Bertolt Brecht and composer Kurt Weill — has been a long time in coming to fruition.

It’s been on the popular singer’s to-do list for a long time. In fact, it was in the fledgling planning stage four years ago, until Vik and James Ralph, executive director of The Shedd Institute for the Arts, learned that the Oregon Bach Festival intended to include the intense piece on the roster of its 2015 season.

“We decided then that it would have to wait quite awhile,” Vik said in an interview earlier this year. “It was a disappointment, though — it’s something I had always wanted to do.”

As the title suggests, the plot of The Seven Deadly Sins is not only complicated, but definitely on the dark side of human nature.

It revolves around a young woman named Anna, who actually is two sisters— Anna 1, the singer, and Anna 2, a dancer. Or is she? Perhaps Anna 2 is really the alter ego of Anna 1, or even a clinically split personality. Maybe it doesn’t even matter, as the Anna character(s) confront the series of classical deadly sins as she/they traverse America, moving from one city to another.

That’s another oddity about the piece, that instead of Germany, the homeland or the original creators, or England, the homeland of the wealthy Englishman who commissioned the piece, or France, where they all joined up to map out the plot, The Seven Deadly Sins takes place in the United States.

Whether you want to see them as one entity or two, the Anna characters set out from their home in Louisiana to seek their fortune, with the goal of returning home wealthy enough to build a little house for their parents there by the Mississippi River.

In pursuit of this dream, the story begins at home in Louisiana and then travels through Memphis, Los Angeles, Philadelphia, Boston, Baltimore, and San Francisco, where in place in turn they confront the cardinal sins of sloth, pride, wrath, gluttony, lust, greed, and envy before returning home, having succeeded in amassing the money to build the little house that spurred the entire experience.

“Brecht often wrote about characters who were struggling to find their way in society,” Vik said. “He examined human morality less in the context of the individual person and more in how that person was formed or affected by the overall economic system and the demands it makes on people’s actions as they try to survive.”

That may be why Anna is portrayed as two different people, or at least as two different aspects of one self, she said.

“The singer has the more logical brain, the dancer is more emotional, and that’s really the same balance that people always have to try to find in making decisions for their own lives,” Vik said.

The Seven Deadly Sins was a complicated piece of work from its inception in 1932. Edward James, the Englishman who commissioned the piece, was married to a ballet dancer named Tilly Losch, who happened to have a striking physical resemblance to Kurt Weill’s life, who was the famous singer Lotte Lenya.

James was aware that Weill intended to set the Anna character on Lenya, so he wrote into the contract that Losch had to have the dancing role, which helped raise the idea even before anything was written that Anna could inhabit more than one character.

Despite its setting in the United States, The Seven Deadly Sins premiered in Paris in June 1933, with George Balanchine in charge of the production and the choreography and — as promised — with Lenya and Losch in the lead roles. The original production was in German, but Lenya did an English translation of the libretto, and that version was performed a few weeks later in London, with the title Anna-Anna.

Because The Seven Deadly Sins is a short creation, taking not much more than a half hour to perform, The Shedd’s program opens with a series of songs from previous collaborations between Weill and Brecht, including Mahoganny-Songspiel, The Threepenny Opera, Happy End, and The Rise and Fall of the City of Mahoganny.

Vik in the past has specialized in interpreting, narrating, and performing works by Brecht and Weill. This production of The Seven Deadly Sins will be performed in English, using a translation by American poets W.H. Auden and Chester Kallman. Vik is joined in the first act by vocalists Caitlin Christopher, William Hulings and Dylan Stasack. The cast of The Seven Deadly Sins also adds singers Cloud Pemble and Alex Mentzel and dancers Sara Stockwell, Jim Ballard, Adam Kelly, Kenady Conforth, and Abigail Howell.

The production also features conductor Robert Ashens, sets by Connie Huston, choreography by Caitlin Christopher, and costumes by Jamie Parker.

The Seven Deadly Sins

When: 7:30 p.m. on Friday and Saturday, Feb. 22-23

Where: Jaqua Concert Hall, The Shedd Institute for the Arts, 868 High St., Eugene

Tickets: $28 to $38 (some discounts; students 50 percent off), available at the box office, 541-434-7000, or online at theshedd.org