English dialogue; English subtitles for the deaf and hard of hearing.
Originally broadcast by PBS Nov. 19, 2014.
A remarkable new story is unfolding in the Arctic. As the ice melts and polar bears struggle to survive, another animal is taking over the polar bear's once dominant role as top predator. An ever-increasing number of killer whales are appearing in Arctic waters. As the polar bear's world is shrinking, the orca's is growing.