Jamie Lee Curtis & Sigourney Weaver in 'You Again': Friends or Rivals?

Jamie Lee Curtis and Sigourney Weaver play former high school rivals who cross paths years later just as younger generation Kristen Bell and Odette Yustman have the same experience in the Disney comedy 'You Again.' The stars tell ET how they bonded on the set -- and had a blast filming with Betty White! "We'd all just sit there with our jaws dropped, because she has it all," says Jamie Lee of Betty. Odette says of the 88-year-old phenomenon, "She's just so vivacious and has this big personality and she's always on it." And Kristen adds, "Not only is she the funniest person in the room, but she's usually the dirtiest. She's somewhat of an open book in that regard." In 'You Again,' in theaters September 24, Kristen plays Marni, a successful public relations pro who is horrified to learn that her brother Will (Jimmy Wolk) is going to marry the girl who made her life miserable in high school, Joanna (Odette). Not content to endure the misery to come, Kristen sets out to expose Joanna's evil ways. Meanwhile, it turns out the bride's jet-setting aunt Ramona (Sigourney) and Marni's stationary mom, Gail (Jamie Lee), have their own less-than-dignified high school history. In no time, the claws come out and old wounds are reopened in this outrageous generational comedy.

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