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Sandra Bullock is bringing "The Heat" this summer -- in more ways than one. Stepping out on Wednesday in London, where she is in town to promote her new buddy-cop comedy with Melissa McCarthy, the 48-year-old actress looked smoking hot in a sexy, little black dress.

Bullock cut a slim figure in the form-fitting frock, which also featured an off-the-shoulder neckline and peekaboo slit above her chest. She paired the LBD with fiery red stilettos and a sleek blowout.

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The vampy ensemble is in stark contrast with the Oscar winner's appearance in "The Heat," in which she plays an uptight FBI agent opposite McCarthy's loose-cannon police detective. Speaking about her co-star in a recent interview with the New York Times, McCarthy said Bullock is a lot tougher than she looks.

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"She's tiny but she's mighty, and she would push back," the "Bridesmaids" star told the newspaper, recalling a scene in which she shoves the "Blind Side" actress (and single mom to Louis, 3). "It was a true fight to the death."

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Bullock, for her part, said McCarthy forced her to rise to the challenge. "She will go for the jugular and, if you're delicate about it, you're going to sink," she joked of her pal. "So you fire back -- you go for the carotid artery."

"You didn't have time to let any insecurity creep in," Bullock added of the hectic shooting schedule. "The first day was like, 'OK, we're not saying anything that's on the page.' Then we get into a slap fight."


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