Ya, iv seen that footage before. It was on the television show called "Amazing Octopus" or something like that. Iv seen the documentary over 2 times on TV.
I think thats the only footage showing an Octopus eating a shark. It was brilliantly captured and very interesting to see an invertabrate eat a deadly Shark. However, of course its a giant octopus. Otherwise, I wouldn't say an Octopuses main prey is the shark. Its usually the other way around. Luckily, giant octopuses have enough strength and size to over match some of its past predators.
That was the voice of Mike De Gruy, and although I believe that footage ended up on other cephalopod specials as well, this originally aired on De Gruy's special "Incredible Suckers".
There were also still photographs published in National Geographic in the late 90s from an expedition off NZ where a sensor of some kind recorded images from a chum-spouting lure lowered down into deep water by a ship. A small shark was circling around the lure and was taken by an arrow squid. Wish I could remember the exact issue!
Someone posted that, a few weeks ago, on a predatory fish forum, where I'm a mod. GREAT VIDEO! For some reason, I cant open up the link that's posted...and, the other video that I saw, there was no audio. So, forgive me if I'm saying something that was already said in the video.
I heard something along the lines of...they kept putting those Dog Fish in the tank, and they'd disappear. No one knew what was going on. So, finally one night, someone stuck around, after hours, to video what was going on...and, surprisingly, they captured that video.
Just goes to show...dont underestimate the cephs. They're gonna take over the world!! lol