Given Terrence McNally's highly theatrical, mostly fictional glimpse of Maria Callas conducting a series of master classes at Juilliard (which she actually did in 1971), it's appropriate that Callas is pronounced "callous."

In McNally's view, Callas was more than merely demanding and strict. She was downright vicious, driving young singers to tears. Jokingly, she refers to them as her "victims" - but she means it.Rather than work with her "Master Class" students on honing their technical skills, she undermines the process by dwelling on her own operatic triumphs and personal tragedies.

While "Master Class" does have its dramatic moments, there's also quite a bit of humor.

The production is a real tour de force for Anne Cullimore Decker. There's not much scenery in Keven Myhre's set, replicating a simple, wood-paneled Juilliard rehearsal hall, but Decker chews up what there is. It's a stunning, absolutely mesmerizing performance.

Director David Mong, who keeps things moving right along, surrounds her with first-rate talent.

Theatergoers accustomed to seeing Anne Stewart Mark in comedies may be pleasantly surprised to hear her operatic prowess as Sharon Graham, who takes a jump-started journey through Verdi's "Lady Macbeth."

Carolyn Talboys-Klassen does a great job as Sophie, a somewhat nervous soprano, who attempts to make her way through Amina's tough aria, "La Sonnambula."

"Good luck," Callas says wryly.

Another pivotal character is Manny Weinstock, the accompanist. Steve Oldroyd, who is well known and highly regarded as a soloist and accompanist for vocalists, is perfectly suited to the role.

But it is Decker who delivers the goods in a stunning performance, especially two 10-minute monologues that conclude both acts.

In the first, while the lights dim on Sophie and Manny, Callas descends into a bravura passage that shifts from arias to Ari Onassis, her crude, foul-mouthed lover.

Jim Craig's lighting and David Evanoff's sound combine to create a dream-like image of an ornate European opera house.

During the second act, there's a similar segment reflecting on others from her past.

Recordings by Callas are neatly blended into both segments.

- Sensitivity rating: Some vulgar language, mainly during the brief references to Onassis.