Season 2 opens with a visit to the New England Aquarium. Included: the 200,000-gallon Giant Ocean Tank; feeding sharks; the mandarinfish, a colorful reef fish native to the Pacific; and the whale shark.

A visit to the Micronesian island of Yap to observe large gatherings of manta rays. Also: a New England Aquarium Dive Club mission off Rhode Island to catch tropical fish that, because of the gulf stream, are thousands of miles from their native waters; a Bahamian expedition to observe tiger sharks.

A Malaysian island that's home to sea turtles; Caribbean and Pacific mangroves (plants that thrives in shallow, salty water); wolffish, an eellike fish with sharp teeth.

The underground rivers of Mexico's Yucatan peninsula; venomous fish; the Greenland shark.

Sea stars (aka starfish); the clownfish. Also: shark-feeding frenzies.

The lobster industry is explored on an excursion with a Maine fisherman. Included: a dive reveals large lobsters. Also: remoras, sucker-equipped fish that attach themselves to sharks and other large creatures; the human-stingray relationship at Grand Cayman.

The Season 2 finale explores Antarctica. Included: the kelp forests of Patagonia; penguins; a dive beneath an iceberg; a 3-ft. jellyfish; an encounter with a leopard seal.