For Every Sylph, There Is a Witch Waiting in the Wings Gia Kourlas on Florentina Holzinger’s “Tanz”

The stage is shrouded in darkness as eerie moans, cackles and chirps pierce the air. The outline of a back gradually becomes visible. As the setting brightens, that shape turns into a woman, Beatrice Cordua, an 83-year-old ballet veteran, seated with her back to the audience. She makes her way to her feet and holds her arms out in welcome.

“Today, I am going to teach you how to govern your bodies,” she says. “Girls, get the barres.”

The first act of “Tanz,” a work by the Austrian choreographer Florentina Holzinger, an audacious star of the European dance and performance scene, is structured like a ballet class, though fittingly in this darkly humorous work, it bristles with tension. Aside from a microphone pack strapped around her torso, Cordua is nude.

As the class progresses from pliés to tendus, Cordua urges the dancers to shed their layers. “I’m hot and I have nothing on,” Cordua says. “Take something off.”

They comply. Soon the stage is a sea of skin.

Opening at NYU Skirball on Feb. 14 for an all-too-brief two-night run, “Tanz” (2019) is a daring exploration of the aging body, the art of discipline and training, and the illusion of ephemerality in ballet. It also embraces terror — for every sylph, there is a witch. Created for an all-female cast of 11, ranging in age from 30 to over 80, “Tanz” digs into what it means to take flight, particularly in relation to 19th-century Romantic ballets like “La Sylphide” and “Giselle.”