Outside the island there is nothing: the world was destroyed by a fog that swept the planet, killing anyone it touched. On the island: it is idyllic. One hundred and twenty-two villagers and three scientists, living in peaceful harmony. Until one of the scientists is found brutally stabbed to death. If the murder isn't solved within ninety-two hours, the fog will smother the island, and everyone on it. But the security system has also wiped everyone's memories of exactly what happened the night before, which means that someone on the island is a murderer, and they don't even know it.