Dr. Jason Barlow, a flying doctor in the Alaskan tundra, flies to a remote Eskimo village in Solitude Bay and saves a sick child through surgery. Two Eskimos then travel four hundred miles by dog sled to bring Barlow back to their pestilence-ridden village of Noonak. Because the men's dogs are half-starved and exhausted, Barlow must take his plane farther than he has ever traveled across frozen land. Barlow is forced to descend when he has engine trouble, and the plane crashes and burns in a bank of snow surrounded by frigid water. Barlow narrowly escapes an avalanche and a polar bear, and swims to land, carrying only a pencil, a notebook, three cigarettes, and a lighter. He continues to log his journey in his notebook and manages to start a fire in a mountain cave, which is the home of two brown bear cubs and their fierce mother. Barlow names the friendly cubs "Tom" and "Jerry" and together they elude the mother bear. Barlow and the cubs survive on muskrat and salmon, but endure prolonged periods of hunger. When a herd of musk-oxen surrounds the camp, Barlow is forced up a tree, until the cubs' growling distracts the oxen and he escapes. When Barlow has been missing three weeks, an Eskimo finds his plane propeller and a team of fliers goes out to find him. Barlow hears one of the fliers' plane, but it passes over him. Barlow then finds a group of snowshoe rabbits and catches one for dinner. Tom and Jerry get entangled with a lion cub, and when Barlow is forced to defend himself against the mother lion, he and the cubs end up in the river. Meanwhile, having no luck in the planes, the search team goes out on sleds and kayaks. The bears then start a fire as Barlow hunts porcupine and fears that he will have to kill Tom or Jerry in order to survive. He then arrives at Noonak, which has been wiped out by the plague, and finds a note from the last survivor stating that he feared he would be killed by the starving wild dogs outside his cabin. The herd of dogs arrives and the cubs are forced up a tree pole. Barlow then climbs to the top of a shack and lights a fire to smoke out the dogs. Soon the mother bear arrives and scares away the dogs, and Barlow's friend Mac arrives in a kayak. Barlow then says good-bye to Tom and Jerry, whom he says kept him from going crazy in the tundra.