Defines cephalopods, such as blue-ringed octopuses and giant squids, and describes their physical characteristics, life cycles, habitats, senses, food, and means of self-defense.

What are cephalopods? -- Cephalopod bodies -- The life cycle of cephalopods -- Where cephalopods live -- How cephalopods sense the world -- What cephalopods eat -- How cephalopods defend themselves -- Up close: blue-ringed octopuses -- Up close: giant cephalopods -- Where can you see cephalopods?.