In the film, Peet's character is dating what "Early Show" co-anchor Harry Smith called a "creepy" plastic surgeon. Her character's ex-husband is played by film veteran John Cusack.
Peet and Cusack have teamed up for two other films, including "Martian Child" and "Identity."
When Cusack appeared on "The Early Show" recently, he said Peet is a "terrific actress."
He added, "What I like most about her is her personality. She's just a really, really fun person to be around. So you spend time with her, and you laugh a lot."
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Peet said she'd like to work with Cusack again in a romantic comedy.
"He's brilliant, he's just a brilliant actor, so he can do anything," Peet said, "but I do feel like it would be fun if we could do something that's more comedic since we both love that."
So what would Peet do if the world ended today?
She joked that she would just hang out with Smith and maybe go for a walk in Central Park.
"I'd love that," she said.
Peet, who has risen through the acting ranks, started her career with Blistex commercials.
"I really did think it was a big deal to book anything," she said. "There was a part of me that, when I was doing the Blistex commercial, I felt like -- it felt as though I was in a movie with Robert De Niro or something like that. (I) didn't realize how far one had to go."
Smith, who shared favorite lines from the 1982 film "Tootsie" with Peet on her last appearance on "The Early Show", serenaded Peet with part of the song, "Kiss Today Goodbye."
"I feel special," Peet said.
"Early Show" co-anchor Maggie Rodriguez said, "I've been with him two years, he's never serenaded me. So you are special."
"2012" is currently in theaters nationwide.