"I didn't take on this project lightly," said Spielberg. "This project has been part of my life since I was a 10-year-old and I first heard the Broadway cast album."
Spielberg is also very familiar with director Robert Wise's 1961 classic, which won 10 Oscars, including Best Picture. But he's clear -- this one is different.
"We didn't remake the '61 film, my friend, Robert Wise, I didn't do that. I, we basically reimagined the Broadway show," said Spielberg.
WATCH: 'West Side Story' 2021 trailer
"West Side Story" is a story of forbidden love. It's set against a rivalry between two street gangs of different ethnic backgrounds. Spielberg chose newcomer Rachel Zegler to play his leading lady, Maria.
"I've always felt like an old soul. And I get told that all the time," said Zegler. "But I was also raised on classic film. And so I feel like a lot of what I think people would call technique but I just call 'what I do,' was born by watching 'All About Eve' and George Cukor's 'The Women' and just watching movies like that, that just informed my love of what I get to do for a living. As much as I embrace modern movies, modern films, modern acting, we would not be where we are without the Joan Crawfords and the Katharine Hepburns of the world. And that's something that I try to remind myself every day."
Spielberg says he's always wanted to make a musical.
"You and I might have had conversations. And we've talked so often about all the different movies and I think you might have been one of the hundreds that have asked me, 'You've done this genre and that. What have you not done?' And I answered you, George. Well, I've always wanted to do a musical. So this time next year, I never have to answer that question again!" Spielberg said, laughing.
"West Side Story" is rated PG-13. It opens Friday, Dec. 10.
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