I'm sure they'll stick to shows that everyone's heard of. I think West Side Story and Dreamgirls are two strong contenders.
I wouldn't expect to see Vanessa Hudgens in The Light in the Piazza.
Or Sarah Michelle Gellar in Grey Gardens.
Or Jon Hamm in Kiss of the Spider Woman.
Or Dermot Mulroney in La Cage Aux Folles.
Other possible (real) contenders would be Mamma Mia!, Annie, Guys and Dolls, Damn Yankees, 42nd Street (trying to lure the Dancing with the Stars crowd), or Camelot.
They'll look for shows with younger leads or lots of younger supporting characters to make sure they cover all the TV demographics. Songs they know, or plots or characters they recognize.
But yeah, I wish they would tackle Ragtime or Big River, both of which I think would adapt well for TV. It's not likely though.
"Jaws is the Citizen Kane of movies."
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