George Clooney Planning the Ultimate Prank?

George Clooney is well known for the jokes that he plays on friends and co-stars, and at the Screen Actors Guild Awards he revealed to Nancy O'Dell that just the thought of his next prank might be causing Brad Pitt to lose some sleep.

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"I actually may not even be working on a prank," George said when asked about a rumor that for the two years he's been planning an elaborate gag for Brad. George went on to joke, "It keeps him up at night. He says things to me like, 'Just don't harm my children.'"

Brad kidded that he's been planning his own prank for five years.

"I thought about a preemptive strike but it would just get too ugly," Brad joked. "I think we should take a truce."

While everyone was appreciative to attend the SAG Awards, none could have been in a better mood that 30 Rock's Katrina Bowden. The actress revealed to Nancy that she just got engaged on Saturday night.

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Katrina showed off her dazzling engagement ring while spilling the details on the proposal.

"It was such a surprise," said Katrina. "We were face down, lying on the bed talking, and that's how it happened. He pulled it out from under the bed."

Contributing Editor of Vogue magazine, Andre Leon Talley, also chatted up the stars on the red carpet, getting them to dish on their fabulous fashion choices. Some celebs like Melissa McCarthy found themselves star struck in the presence of Vogue's former editor-at-large.

"I'm so bewildered to meet you," Melissa admitted.

Tune in to ET on Monday for Andre's Best and Worst dressed.