"Three Decembers," Friday-Sunday, May 29-31, at the Alliance Theatre. Tickets: $35, plus fees, available at atlantaopera.org or by calling 404-881-8885. The Alliance Theatre is in the Woodruff Arts Center, 1280 Peachtree St. N.E,. Atlanta. ‎The opera will be performed in English. atlantaopera.org; 404-881-8885.

After a year of mostly classic works by such masters as Puccini and Mozart, the Atlanta Opera closes out its 2014-2015 offerings with "Three Decembers," the Southeast premiere of a 21st century opera by composer Jake Heggie and librettist Gene Scheer.

The 90-minute presentation is part of an ongoing commitment to contemporary opera by Tomer Zvulun, general and artistic director of the Atlanta Opera. It is the first in the Discoveries Series, which continues this fall with "Soldier Songs," by David T. Little.

Made possible by a grant from Rosemary and John Brown, the Discoveries series stages productions of new work in venues around the city, including at the Rialto Theatre downtown, Oglethorpe University, and the Alliance Theatre where "Three Decembers" performances will take place.

Heggie and Scheer, currently working on another new opera based on “It’s a Wonderful Life,” have collaborated often, notably on “Moby-Dick,” which premiered in Dallas in 2010.

While the two had to strive to reduce that sprawling novel to a manageable size, they had the opposite challenge in “Three Decembers,” which began as a short script by playwright Terrence McNally.

Scheer expanded the 14-page story, but retained the episodic structure. The action visits a small family — a brother, sister and their mother — every 10 years, checking in with them at Christmas in 1986, 1996 and 2006. “We see how their lives are affected by mental illness, AIDS and just getting older,” said Heggie.

At the center of Scheer’s libretto is Madeline Mitchell, a Broadway actress who must struggle to cope after her husband commits suicide. Revolving in her orbit are her estranged gay son and her unhappily-married daughter.

The story resonated with Heggie, whose own father committed suicide and whose mother raised four children by dint of willpower.

“She was a nurse, she was 39 years old, with four kids, and she had to go back to work, and back to school, to get a better job, to support us,” said Heggie, in a phone conversation from his home in San Francisco. “We saw her very little.”

The opera also dramatizes the AIDS crisis, when thousands died each year and families were broken apart. Heggie knows of young singers who have performed “Three Decembers” but were unaware of the peculiar, tragic paranoia of the 1980s — because they weren’t born yet. “To have lived through the ’80s and ’90s with that sort of fear and stigma, the terror, and the way people were treated, is so horrifying,” he said, “that the only way you hopefully keep something like that from happening again is you have to keep telling the story.”

Scheer, 57, a New Yorker, and Heggie, 54, a Californian, work together without regard to the continent that separates them. Their unique method involves much email, and the occasional get-together. (During the Atlanta premiere of “Three Decembers” they will rent a studio with a piano somewhere and get to work.)

Every opera always starts with Scheer’s words, words that he hopes will inspire music. “If it doesn’t inspire music it’s not doing its job,” said Scheer. “The great thing about an old trusted colleague is we can say anything, we can discuss it, we can say why it doesn’t work.”

The two are known to change the libretto right up until the first performance, and even afterward.

"Three Decembers" will be performed by mezzo-soprano Theodora Hanslowe as Madeline Mitchell; baritone Jesse Blumberg as Charlie, the son; and lyric soprano Jennifer Black, as the Beatrice, the daughter. The chamber-style orchestra is comprised of 11 players on winds, strings and percussion, and includes two pianists. "It doesn't feel small," said Heggie. "It feels very big emotionally and sound-wise."

In this age of the microphone, a whispered song can be broadcast at thunderous volume to an audience of thousands. Heggie has nothing against amplification. But he wonders why, even on Broadway, the sound must be quite so loud.

He points out, that while opera can’t match the broad appeal of pop music, still the sound of a powerful voice, undistorted by amplification and electronic processing, will never lose its appeal.

Listeners, even brand new listeners, are charmed. “When they hear it,” said Heggie, “their response is this huge sigh of relief at the natural beauty of the instrument.”