“West Side Storyis the greatest American musical.”

But just because something’s great doesn’t mean it’s not ripe for a little re-invention.

A large part of that came in a new script from Pulitzer Prize winnerTony Kushner.

West Side Story

‘West Side Story’.Niko Tavernise/20th Century Studios

Here, Spielberg and the cast take us behind three of the biggest shifts.

Spielberg was very aware of that.

“The best number in the ‘61 film was ‘America,'” he notes.

West Side Story

Mike Faist in ‘West Side Story’.Niko Tavernise/20th Century Studios

“The choreography and the camerawork between Robert Wise and Jerome Robbins is unrepeatable.

That left Spielberg with one option: completely re-imagine the number to avoid that comparison.

He and Kushner devised the alternative we see on screen.

West Side Story

Rita Moreno in ‘West Side Story’.Niko Tavernise/20th Century Studios

“Why don’t we take it out into the streets in broad daylight?”

Spielberg explains of his thinking.

“It was a giant community and everyone coming together to celebrate this.

It felt like we were part of something so much bigger than just us.”

“We shot it during a heatwave,” explainsAriana DeBose, who portrays Anita.

It felt like a love letter to the city.

But I burned holes in my shoes.”

“They had to CGI my sweat out,” adds Alvarez.

“Typically, we’re talking about how Latinos are drug lords or drug mules.

And we have all these problems, and we’re not educated,” she says.

You got to know these people and their light, not just their dark.

It’s a really beautiful duality.

You get to know this community.

I’m really proud of that."

It also became a showcase for some of Jerome Robbins’ most recognizable and oft-referenced choreography.

It’s more akin to Javert and Valjean’s face-off inLes Miserablesthan the number as originally conceived.

They fight over a gun Riff plans to bring to the rumble on a rickety pier.

“In the play, of course, ‘Cool’ is what they do when they cool off.

“We very much wanted that to be our own,” adds Spielberg.

‘Do not bring that gun to the fight.'”

Elgort describes the number as a game that suddenly gets out of hand.

“The most interesting part about that dance was the storytelling aspect of it,” adds Mike Faist.

“Here are these guys that are brothers, and it starts as this cat and mouse game.

“‘Somewhere’ had to be about [Valentina] mourning the loss of her husband.

It also had to be about the last desperate connection between Maria and Tony.

It had to be about the aftermath of Anita losing Bernardo.

It is about: There’s a place for all four of those characters.

Maybe there is, maybe there isn’t, but she’s singing for everyone, including herself.”

Ultimately, the actor says, the Bernstein estate pushed back on her vision of a more piqued delivery.

“Her vocal informed Anita’s journey for me,” says the Broadway alum.

“I felt some of that anger, whether or not she was actively singing it.”

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