Architect Tom Faraday is determined to finish the high-concept, environmentally friendly home he's building in Norway--in the same place where he lost his wife, Aurelia, to suicide. It was their dream house, and he wants to honor her with it.

Lexi Ellis takes a job as his nanny and immediately falls in love with his two young daughters, especially Gaia. But something feels off in the isolated house nestled in the forest along the fjord. Lexi sees mysterious muddy footprints inside the home. Aurelia's diary appears in Lexi's room one day. And Gaia keeps telling her about seeing the terrifying Sad Lady. . . .

Soon Lexi suspects that Aurelia didn't kill herself and that they are all in danger from something far more sinister lurking around them.