So somehow, somewhere, someone recently started a rumor that Kevin Costner had rescued his wife from a shark attack. Seems plausible, given the spate of recent celebrity aquatic heroics: Hugh Jackman did actually help clear his kids and others from the surf in Australia when a shark was spotted nearby, and Heidi Klum saved her kids from a dangerous riptide.

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But Costner? Not so much. At least he has a sense of humor about it, though. The man himself took to Facebook to address the rumor by posting a photo from infamous bomb "Waterworld" along with the caption, "Although I do feel well-versed in the art of marine combat, I've fought zero sharks as of late." So there you have it. 

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