A Bear like no other . . .

An accomplished Inuit hunter at fifteen, Nick Thrasher is about to bring home a caribou when he loses the meat to a fearsome creature never before seen in the wild. It's half grizzly, half polar bear. Wildlife experts will soon be calling it a "grolar bear."

Back home in his Arctic village, Nick receives a letter from Ryan Powers, the half brother he has never met. On assignment for National Geographic, Ryan is coming north to photograph migrating caribou, and proposes Nick join him on a raft trip down the remote Firth River. Their adventure is barely underway when both are thrown into the freezing river, under a ceiling of solid ice. With nothing but Nick's knife and the clothes on their backs, Nick and Ryan fight to survive in a world of caribou, wolves, and grizzlies. All the while, the dreaded grolar bear stalks the land.