A plane crashes on a desert island and the only survivors, a group of schoolboys, assemble on the beach and wait to be rescued. By day they inhabit a land of bright fantastic birds and dark blue seas, but at night their dreams are haunted by the image of a terrifying beast. As the boys' delicate sense of order fades, so their childish dreams are transformed into something more primitive, and their behaviour starts to take on a murderous, savage significance.