Who wore it better? Hands down, Heather Graham! On Tuesday, May 28, The Hangover: Part III cast went for a swim at Ipanema beach in Rio de Janeiro, and appeared to be jokingly competing in a hot beach bodies contest.

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Graham, 43, flaunted her flawless figure in a red print bikini while splashing in the water. The ageless actress showed off her slim, toned bod while soaking up the sun with a big smile on her face.

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Not to be outdone, costars Zach Galifianakis and Ed Helms strutted their stuff in tiny colorful Speedos. Galifianakis, 43, and Helms, 39, proudly displayed their hairy chests for photographers while walking along the beach.

Costars Ken Jeong and Justin Bartha didn't follow the comedians' style, and opted for longer swim trunks. But the real party pooper appeared to be Bradley Cooper.

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The 38-year-old actor kept his T-shirt on while joining his costars on the beach. Cooper tied up his long hair into ponytail, and relaxed by sitting in the sand and watching the Wolfpack fool around.

This article originally appeared on Usmagazine.com: Heather Graham's Hot Bikini Body: Hangover III Costars Compete in Speedos