Fact: Sharks can smell even a drop of blood from quarter of a mile away. What better way to test the safety of a Gillette ProGlide razor versus a disposable razor? Labeled as The World’s Scariest Shave, the side-by-side demo was shot entirely live underwater in the Atlantic Ocean, using professional divers and shark experts. Nothing was doctored or altered. Even the razor cut was real, which drew instant reactions from over a dozen wild 14-foot tiger sharks and lemon sharks.