Jeff Bridges returns to the franchise.
"Fabulous! Very exciting!" Bridges said. "This music you're hearing now is a major part of the excitement."
The film follows a highly sophisticated program, Ares, played by Jared Leto, who is sent from the digital world into the real world on a dangerous mission.
"It's really a film that's meant to be seen on the big screen. The biggest you can find," Leto said.
He also paid tribute to Bridges and his work: "I mean 40-years something ago, he started working on 'Tron,' so incredible to be here."
The stars got to watch the film with a packed house for the first time at the TCL Chinese Theatre on Monday.
"My parents are here," said Greta Lee. "I didn't really prime them. I was watching them, and I think they're in a state of shock. They are somewhere here. I hope they're okay. Mom, Dad?"
Arturo Castro says as cliche as it sounds: "I've literally dreamt of things like this."
Rock group Nine Inch Nails was tapped to make the soundtrack, and in true Hollywood fashion, the band surprised guests with a live performance.
"Tron: Ares" opens in theaters Friday, Oct. 10.
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