Two-time Emmy Award-winning producers Greg Marshall and Birgit Buhleier feature polar bears, ringed seals and narwhal -- and the scientists who study them -- in this spectacular one-hour documentary. Filmed using the National Geographic Critterman which they developed, they include University of Alaska's Dr. Brendan Kelly's work on the ringed seals of Prudhoe Bay and an international team studying narwhal in the waters of Baffin Island.  (ARC211, $19.98)