Killer Squid, about the Humboldt squid, the most advanced of the mollusca, but which live only a year (until they breed) and actually go into cannibalistic feeding frenzies. The tentacles have 36000 teeth and the food is manipulated with a beak. But they can hunt in schools, and actually have social behavior not seen before in cephalapods. They have good problem solving ability, like octopuses. Over-fishing may have created the impression that they behave aggressively. This is as high as invertebrate evolution ever got.