High above the arctic circle, on a remote Canadian island, an American sports hunter shoots what he believes is a polar bear. He is mistaken. His Inuit guide has never seen an animal like this before. The killing unleashes an investigation by the Canadian authorities. But no-one can tell exactly what he has shot. The hunter is under threat of prosecution for a crime he says he didnt commit. Scientists pour over the only evidence they have the corpse of an animal theyve never seen before. With each new discovery the mystery deepens as they try to discover the exact species of this animal.