If your heartstrings aren’t thrumming a few numbers into into this sister act, then I’m sorry to say you simply don’t have a heart. “Broadway the Calla-way” brings some of Broadway’s most emotional songs together with two of the greatest voices to thread the boards. Liz and Ann Hampton Callaway gloriously display the power of siblings harmonizing. They seemingly possess quite different voices. Liz has a muscular yet elegant Broadway soprano, and Ann has a wide-ranging jazz monster of a voice.

And yet, when they harmonize, the blending is utterly seamless, sometimes to the point of not being able to determine who’s singing what vocal line. You can hear this best in a medley of “The Schuyler Sisters” and “Lullaby of Broadway” early in the show. They also have great comic chemistry, doing a barbed version of Gypsy’s “Some People” that’s as hilarious as it is mellifluous – with props no less.

Both sisters soar solo for stretches of the show. Ann shines with an emotional and detailed reading of the tender “If He Walked Into My Life” from Mame, and Liz does a version of “The Music and the Mirror ” from A Chorus Line that can hold its head up with any other version of the song, perhaps not surprising since it is most often sung by dancer-actors rather than a nonpareil singer-actor like Liz.

It’s also clear that the sisters have a lot of gay men in their circle! When word got out that they were putting a show of Broadway song together, oh boy did they get phone calls, e-mails and texts offering suggestions of duets they absolutely must do together. They include a bunch of these suggestions in what they call they “The Huge Medley.” I won’t give away the exact songs – they’re just too delicious – but let’s just say they involve major gay icons belting their brains out. So gay and so fun! Highly recommended.

For tickets, click here.

To learn about Jonathan Warman’s directing work, see jonathanwarman.com.