Madelene is married to Burden, an ambitious zoologist, comfortably off and a chronic alcoholic. The ape is Erasmus, who comes ashore in London from sailing boat called The Ark. Burden aims to use the ape as the means to fulfil his ambition to direct the London Zoo. Erasmus and Madelene elope.

One snowy day in Copenhagen, six-year-old Isaiah falls to his death from a city rooftop. The police pronounce it an accident. But Isaiah's neighbour, Smilla, suspects murder. She embarks on a dangerous quest to find the truth, following a path of clues as clear to her as footsteps in the snow.