In our (otherwise bleak) midwinters, the Chorus of Westerly annually dazzles, entertains and warms us with its "Celebration of Twelfth Night" productions.

In particular, the last four editions of "Twelfth Night" have successively provided a distinct chapter in a five-part story arc - meaning this year's rendition in the George Kent Performance Hall in Westerly is the final piece in a wondrous and labyrinthine narrative puzzle.

There will be seven performances: one Friday and three each on Saturday and Sunday.

As conceptualized by Harvey Blanchette and coordinated by director Darren Wood, the ongoing story is set in a fantasy world of four different empires. There's a decided Light/Darkness motif and a phantasmagoric mythology at hand - but the essential core characteristics of the traditional "Twelfth Night" celebrations are absolutely part of the show.

Since each of the previous four productions took place in a different one of the geographical empires, one of the big questions for the "Twelfth Night" team was, in a story sense, where and how it will all resolve.

"Ultimately, we end up in a new location - the Realm of Chaos," Wood says. "At the same time, we're definitely going back, and we'll see some characters we've met along the way. But the production does stand alone, too."

Yes, by design and with consideration for audience members who couldn't necessarily make each edition over the years, all of these "Twelfth Night" efforts have worked as stand-alones while dovetailing into the larger theme.

This also marks the first "Twelfth Night" for new Chorus of Westerly music director Andrew Howell.

"The biggest thing for me was the day-to-day preparation: getting ready for the musicians," Howell says. "For one thing, there's quite a bit of new music this year. We'll always have the 'Twelfth Night' stuff from the classical repertoire, but we're doing a lot of little things that are different with material arranged for brass and chorus."

Both men agree that, while hectic, the process of shaping a new "Twelfth Night" is exhilarating and rewarding.

"I think the 'adapting as you go' is part of the fun in this sort of art form," Wood says. "There are so many disciplines involved. You've got stilters and actors and opera singers and a huge chorus and giant puppets. ... We just found out we're going to have a Charleston involved. And everyone involved brings these incredible skills to the table, and you end up with this stew of greatness."

One substantial new "Twelfth Night" presence is soprano Teresa Wakim, who plays the female lead Ayla. She's a Noank native who graduated from the Williams School and has been shining in vocal competitions across the U.S. and Europe.

"Teresa is a wonderful soprano and a fantastic addition to the chorus and the cast," Howell says. "She a genuine, rising star in the international music scene, and we're so happy she's part of this."

The Chorus of Westerly's "Twelfth Night," which started in 1975, has become and will continue to be a January tradition. But does Wood feel there's a bit of a melancholy sense, considering the 2013 show is the final of the Blanchette's five-year Magnum Opus?

"To be honest, I don't think I've felt sad," Wood says. "Now that it's been mentioned, maybe I should. But every time I think of 'Twelfth Night,' each is a different challenge unto itself. Just doing one is a huge accomplishment. In any context, they're all a huge blast."

The Chorus of Westerly's "A Celebration of Twelfth Night," 7:30 p.m. Friday and 1, 4 and 8 p.m. Saturday and Sunday, George Kent Performance Hall, 119 High St., Westerly; $17-$70; (401) 596-8663, chorusofwesterly.org.