In this video a surfer hitches a ride behind a shark, after getting the shark to swallow some chunks of meat attached to a fishing line. It looks like it was shot in southern California, and we do get some big sharks around here occasionally. Just last week a guy was killed off the coast of San Diego by a great white. But this video looks obviously fake. As many of the youtube comments point out, you can see the wake of a boat off camera in front of the shark fin.
I don't have any information about who made the video. At the end, the word "Notorious" appears on the screen, but I don't know who or what that is.