Iceland, November 1967. Fourteen-year-old Marsi has a secret penpal - a boy who lives on the other side of the country - but she has been writing to him in her older sister's name. Now she is excited to meet him for the first time. When the date arrives, Marsi is prevented from going. During the night, her sister Stina goes missing - her bloodstained anorak later found at the place where Marsi and her penpal had agreed to meet. November 1977. Stina's disappearance remains unsolved. Then an unexpected letter arrives for Marsi. It's from her penpal. Desperate for news of her missing sister, but terrified that he might come after her next, Marsi returns to her hometown and embarks on an investigation of her own. But Marsi has always had trouble distinguishing her vivid dreams from reality. As insomnia threatens her sanity, it seems she can't even trust her own memories...