It is May 1977, a quiet house in the English Cotswolds. Emily,an emotionally fragile,gentle, nature-loving girl, is approaching her eighteenth birthday. Her father, Martin, has become worried about her since the death of her mother, as she has begun to walk in her sleep and says she sees her mother’s ghost.
When Martin gets the chance to join his friend Barnaby on an archaeological dig on Crete, he welcomes Emily’s suggestion that she and her older brother David join him out there. Staying with their father’s Greek friends, Emily and David are introduced to the thoughtful young son of the family, Petros, who is prepared to go along with David’s constant quest for fun and girls but who falls in love with the shy, distant Emily.
When the siblings notice a mysterious island in the bay, now deserted and a source of superstitious fear among the local villagers, David is eager to explore it, despite Petros’ warnings, but Emily feels afraid and troubled. Eventually the island draws them in, and soon Manolis, a local fisherman who is obsessed with the island for his own reasons, leads them all into a terrifying adventure. The story winds its way through Cretan labyrinths to a strange and surprising conclusion.