Schooling gray reef sharks (Carcharhinus amblyrhynchos) at Fakarava's south pass (Tomakohua) in French Polynesia. This is likely the best pass in the world to see aggregating reef sharks. We normally dive the south pass on the incoming current. In the strong current, the sharks enter a sort of a dormant state, circling in place in order to pass water over their gills with the minimum effort. On a typical dive, one might see upwards of 650 sharks in 3 big "walls." I've been to the south pass of Fakarava three times now, and it is one of my favorite dive destinations in the world.
Video shot with Blackmagic Design Pocket Cinema Camera, Panasonic 8mm fisheye lens, Nauticam underwater housing. CinemaDNG @ 24fps.