A Humboldt squid rockets up out of the darkness, meeting Bob Cranston in the middle of a cloud of krill.

(Airs Sunday, June 28) Underwater cameraman Bob Cranston explores the remarkable world of marine creatures called cephalopods -- squids, cuttlefish, octopi, and nautili.

There is one less mystery in the deep sea: for the first time, two Japanese researchers have finally photographed a live giant squid in its ocean home.

Bob Cranston waved off advice from local fishermen and caught some of the most memorable footage ever captured of the giant and aggressive Humboldt squid.