The best moments in Satchmo at the Waldorf come when the audience at the American Conservatory Theater is cast as the crowd at the Waldorf Astoria of the play's title. "White people don't stop coming to see me play," announces Louis "Satchmo" Armstrong from his dressing room, having just performed for a hotel crowd so white they resembled a "carton of eggs." Then, addressing his current audience in San Francisco, he adds knowingly, "And it doesn't look like they ever will."

Satchmo at the Waldorf was written by Wall Street Journal drama critic Terry Teachout, a scholar of Armstrong, and is directed by Gordon Edelstein. An off-Broadway hit, it's received high praise in Chicago, Los Angeles, and elsewhere. John Douglas Thompson, the Obie Award-winning Canadian-American actor, portrays the entirety of the cast, and mostly that's a 69-year-old Armstrong, whom he plays with a gait like a wounded King Lear and a voice perfectly bottled from countless recordings of the musician.

After we're acquainted with Armstrong, Thompson straightens his back and changes form in a tonal switch that makes the audience sit up. The lights shift, the mirrors on Lee Savage's set become windows from a New York office building, and Thompson is Armstrong's longtime manager, Joe Glaser. A blustery Jewish hard-ass involved with Al Capone's Chicago mafia, Glaser is Armstrong's' closest confidante, but he will eventually leave the musician who made his business with nothing. "I am Louis, and Louis is me," Glaser announces in a gesture to the form.

Thompson's boisterous, gravel-throated Armstrong is a joy to watch, but so, for that matter, is his foul-mouthed Glaser, and their relationship is at the center of the play. Is Glaser Armstrong's friend, a father like he's never had? Or is he something more sinister: A profiteer, or worse — as the play insinuates — a modern slave master working his property to death?

As an acting bonus, Thompson briefly embodies an effete and almost sneering Miles Davis, one of Armstrong's sharpest critics. Satchmo's crowd-pleasing antics — singing, grinning, handkerchief waving — were in part Glaser's influence. But, by the play's reckoning at least, they were genuine. Armstrong, he professes, believes in a happiness behind the blues.

Locating oneself in the action of Satchmo at the Waldorf can be frustrating. What's the climax to which we're looking forward? Armstrong changing out of his performance duds and into street clothes? The musician, who cleans his instrument throughout, maybe playing a number?

Perhaps that hope is a trap — a wish for more "Hello Dolly" Satchmo entertainment. Regardless, the play cleverly thwarts it. Really, the resolution we're looking for is from Armstrong's relationship with Glaser. It seems that through him, Satchmo can come to some sort of ambivalent understanding with a white America that loves — and does not — love him.

By the time Satchmo gets there, we don't want him to go. But don't worry: The audience is made to understand that the show he's just finished isn't his last at the Waldorf. The engagement there will continue, and he's just going upstairs to get some well-deserved rest now that black people, or at least he, can stay at the hotel. Until tomorrow night, he says in a parting wink at his audience.

Satchmo at the Waldorf plays through February 7th, $20-$105, American Conservatory Theater, 415 Geary Street. Find tickets here.