Ten-year-old Nicolas lives with his mother in a remote village beside the ocean, inhabited solely by women and boys his age. In a hospital overlooking the sea, all the children receive a mysterious treatment. Nicolas is the only one to question it. He feels that his mother is lying to him and would like to know what she does with the other women at night on the beach. What he discovers is just the beginning of a long nightmare. But Nicolas will discover an unexpected ally in a young nurse at the hospital.