When Tartelin answers an ad for a personal assistant, she doesn't know what to expect from her new employer, Marianne, an eccentric elderly woman. Marianne lives on a remote island that her family has owned for generations, and for decades her only companions have been butterflies and tightly held memories of her family. But there are some memories Marianne would rather forget, such as when the island was commandeered by the British government during WWII. Now, if Marianne can trust Tartelin with her family's story, she finally might be able to face the long-buried secrets of her past that have kept her isolated for far too long.

Romilly Kemp and her eccentric painter father have happy but sheltered lives in a ramshackle mansion in the English countryside. When her father finds fame with a series of children’s books starring Romilly as the main character, everything changes: exotic foods appear on the table, her father appears on TV, and strangers appear at their door, convinced the books will lead them to a precious prize. But as time passes, Romilly’s father becomes increasingly suspicious of the outside world until he begins to disappear within himself. She returns to his illustrations, looking for a way to connect with her ailing father, and finds a series of clues he has left just for her. This treasure hunt leads her to a shocking secret that is crucial to understanding her family.