“A child ought never to see the jagged edges of the world,” utters one character in “But the Giraffe, a Curtain Raiser to Hans Krasa’s Brundibar,” the first half of Tony Kushner’s powerful, eerily chipper new collaboration with mythic children’s-book illustrator Maurice Sendak.

Mr. Kushner’s plays have exposed plenty of kids to plenty of jagged edges, from radiation poisoning (“Slavs!”) to Southern racism (“Caroline, or Change”). In “But the Giraffe …” and the 1938 children’s opera “Brundibar,” however, he has upped the stakes considerably from his recent “Only We Who Guard the Mystery Shall Be Unhappy,” in which Laura Bush reads to a classroom of dead Iraqi children. The children here are staring into the maw of the Holocaust.

“Brundibar,” composed by Hans Krasa, is best known for being performed 55 times at the Thereseinstadt concentration camp during World War II. (This was the “model ghetto” that Nazi propagandists set up as a more presentable version of the camps for outside eyes.) Messrs. Kushner and Sendak collaborated on a stunning children’s-book version of the story in 2003, and now they have revised it for the stage and paired it with a new Kushner play. Both have been directed simply and stirringly by Tony Taccone for the New Victory.

Billed as a curtain-raiser, Mr. Kushner’s “But the Giraffe …” is in fact nearly as long as “Brundibar.” The story of a young girl agonizing over how to pack her suitcase before a trip, it is a parable about choosing between one’s own comfort objects and items that may one day bring comfort to others. Those alternatives are depicted here as a beloved stuffed giraffe and, at the request of her uncle, a brand new opera named “Brundibar.”

It gradually becomes apparent that this trip is not a voluntary one and that the choice of objects has major ramifications. (In real life, an incoming inmate smuggled the score of “Brundibar” into Thereseinstadt, where Krasa had already been interned.) The unnamed girl (played by an appealing Danielle Freid) is guided in her decisions by various family members, including a nefarious imaginary friend and a grandmother brimming with factoids about giraffes. These facts also pertain – somewhat transparently – to the Jews: Giraffes form a tribe unto themselves. They are intelligent and curious. And “it’s said they face death quietly.”

Like so much of this double bill, the girl’s dilemma works equally well as a tidy story for children – the New Victory has deemed the production appropriate for ages 8 and up – and a sobering metaphor for adults. (It evokes a rather perverse children’s-theatre version of “Sophie’s Choice,” for one thing.)

Rare is a work of Mr. Kushner’s that wouldn’t benefit from some pruning, and this holds true even for the 35-minute “But the Giraffe …,” which reportedly was added to the evening at the last minute. And the giraffe-Jew comparisons become fairly obvious, at least by adult standards. But perhaps a little spoon-feeding makes it easier for the writers to downplay the Holocaust imagery that Mr. Sendak used so devastatingly in the “Brundibar” book.

Snippets of Krasa’s alternately sharp and voluptuous score can be heard throughout “But the Giraffe …,” but the full score (played superbly by a 13-piece orchestra) is a pleasure to listen to, alternating in style between the astringent oompah-pah melodies of Kurt Weill and the surging folk-themed tunes of Dvorak and Smetana. Along with Mr. Taccone’s efficient direction, this music keeps Adolf Hoffmeister’s story, about children banding together to defeat the villainous Brundibar, from becoming too saccharine.

The story is fairly simple: Young Pepicek and Aninku (Aaron Simon Gross and Devynn Pedell) go to town to buy milk for their sick mother. But they have no money, and the organ grinder Brundibar (Euan Morton), has cornered the market on singing for coins. With the help of a dog, cat, and sparrow, the youngsters eventually mobilize the local children and run Brundibar off by singing en masse. Help can come from anywhere, they sing – “Sometimes it’s all around, / Sometimes it must be found.”

Mr. Taccone’s cast could not be improved upon: The two children sounded marvelous, and the adults (many of whom also appear in “But the Giraffe …”) were unafraid to look as silly as the material requires. As Brundibar, Euan Morton laces his kid-friendly hiss worthiness – one youngster took a swipe at him as he fled through the audience during a recent performance – with just the right amount of malice. Mr. Kushner has sharpened Brundibar’s song about Pepicek and Aninku with an ominous new level of vitriol:

Little children, how I hate ’em,
How I wish the bedbugs ate ’em!
How their parents overrate ’em!
If they’re rude exterminate ’em!

Mr. Taccone has blended the children’s chorus (assembled from Rosie O’Donnell’s arts education organization) into the action fairly seamlessly, although the children’s diction could be better. And if Mr. Sendak’s visuals can’t measure up in complexity to those in the “Brundibar” book, they give the New Victory Theater stage the look of a magical picture book, albeit one with very real shadows.

Mr. Kushner realizes that a purely happy ending would be morally indefensible. And so he added an epilogue in which the vanquished Brundibar resurfaces to remind the audience that “bullies don’t give up completely. / One departs, the next appears.” (In the book, this appears scribbled on an advertisement for a 1944 mounting of the opera in Thereseinstadt.)

This chilling coda might well go right over the heads of youngsters more accustomed to “Lemony Snicket” and “Harry Potter” than Anne Frank and Elie Wiesel. It sounds much like the sort of “I’ll be b-a-a-a-a-c-k” tagline that promises a sequel. In the sequel to “Brundibar,” Messrs. Kushner and Taccone make hauntingly clear, the dog and cat – not to mention the giraffe – will not be making the trip.

Until May 21 (229 W. 42nd Street, between Broadway and Eighth Avenue, 646-223-3065).