In Churchill, Manitoba, polar bears gather each fall waiting for the ice to freeze on the Hudson Bay so they can stalk out to their winter habitat where they hunt their prey. Until then, the bears prowl through the town, scavenge through the dump, and often begin to starve.

Beryl is a nature photographer on an expedition to photograph these hungry bears from a small iron cage. She has never photographed animals larger than deer and has usually worked in zoos, not in the wild. Now she is challenging herself to face the world's largest land carnivore in the bone-aching cold of an unforgiving terrain that offers no protection should the cage fail.

Beryl's companions include three men: David, a video cameraman who would prefer a tropical assignment; Butler, a naturalist and writer; and Jean-Claude, their enigmatic guide. Even before they leave Churchill their group runs into trouble, for despite their state-of-the-art survival gear and high-tech gadgetry, Beryl and her companions are not prepared for the numbing, killing reality that awaits them in the cage.

Miles from Churchill, the expedition goes disastrously wrong and they must try to make their way past starving bears, across frozen tundra and treacherous ice floes, to the warmth and safety of town. The Cage is a gripping adventure of a woman who goes to a dangerous place in search of herself and finds she must draw on her every strength in order to survive.