A huge hammerhead shark circled a couple of paddleboarders off the coast of Florida ... and the terrifying encounter was all caught on video.
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The footage -- shot Sunday between the Bahamas and Lake Worth, FL -- first shows a woman on a paddleboard in the middle of the ocean being followed by a shark ... with a fin rising above the surface and getting super close to her board.
The shark appears to circle the paddleboard, then it goes over and checks out another paddleboarder.