Ryan Murphy vs. Shonda Rhimes: Battle of the Fall TV Season

TV networks are bringing out their big guns for upfronts, making announcements about their fall lineups and there's a lot to be excited about.

TV networks are bringing out their big guns for upfronts in New York, making announcements about their fall lineups and there's a lot to be excited about.

The show stirring up the most buzz is Ryan Murphy's Scream Queens, starring Emma Roberts, Lea Michele, Abigail Breslin, Ariana Grande, Nick Jonas and Jamie Lee Curtis.

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"Scream Queens is dope," Jamie told ET.

"It's like Scream meets Mean Girls," Lea said. "You're going to like it. Trust me."

"It's very Heathers meets Halloween," said Emma. "I was instantly obsessed. There's a lot of girls on the cast and a lot of amazing fashion."

In true Ryan Murphy fashion, the show has been shrouded in secrecy, but Ryan gave ET a preview of the show earlier this year, saying that it will center on the "world's meanest sorority" when a "series of bad things" begin to happen.

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In contrast, the entire country knows the plot to Ryan's upcoming project, American Crime Story: The People V. O.J. Simpson.

Selma Blair is the latest addition to the star-studded cast, playing Kris Jenner in the show, and Ryan told ET why she's the perfect choice.

"She has a great occasion to be dramatic and show a sympathetic, dramatic side to Kris Jenner that I wanted to tell," Ryan said.

Selma will be playing opposite David Schwimmer, who stars as Kris' late husband, attorney Robert Kardashian.

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"I was also lucky enough to speak to Kris Jenner and try to get to understand who Robert was," David told ET. "I'm really excited."

Of course Ryan isn't television's only uber-producer. Shonda Rhimes is also making a splash.

With McDreamy’s shocking death on Grey's Anatomy and Scandal's upcoming finale, the cast members are on the edge of their seats.

"I hear that she's recut everything," Scandal's Bellamy Young said of the finale. "Shonda's had a vision and changed some stuff, so I'm excited to find out just what happens Thursday night."

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Shonda explained the move, saying, "We were done and I sort of woke up one morning and thought, 'No,' and we went back and did something different."