On the edge of a quiet fishing village in a remote archipelago lives a family bound to the sea. Jim and Mary share their home with their son Alfie, and with Lucy, a mysterious eleven-year-old girl with striking white hair and visions no one else can see. Nobody knows where she came from. Her gifts spark curiosity that soon turns to suspicion among the villagers, then to whispered rumours and cruelty in the schoolyard, as news of a distant war makes the islanders fear anyone who seems different. When Lucy meets Milly, her secret imaginary friend, the two girls set off on a magical quest to uncover the secret behind her mysterious powers.

Inspired by 'Listen to the Moon' by Michael Morpurgo, the author of 'War Horse', the film is set on the Isles of Scilly, a scattering of islands off the south-western tip of England, where shipwrecks were once common, and the tide drops low enough to cross between islands on horseback. Olivier Clert's first feature tells the story through Lucy's eyes, painting it all by hand in warm dawn and dusk light. It is a heartfelt journey that tests the bonds of friendship and courage, and a gentle, timely story about the fear of strangers.