The Wolfpack is back and how! The Hangover Part 2, with Bradley Cooper, Zach Galifianakis and Ed Helms, scored the biggest opening of an R-rated comedy ever.  Its box office estimate for the five-day Memorial Day weekend is $137 million.

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For movie-goers with kids, Kung Fu Panda 2 proved a popular choice.  It came in second, with an estimated $68 million take for the holiday weekend.

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