On a prison island for the world's worst criminals, a prisoner is set for execution. After absorbing multiple surges of electricity and nearly knocking out power to the entire island, the prisoner dies. The prisoner is buried in the graveyard with a single marker bearing only three digits: 489. After the burial, a violent storm rocks the island and a staff member goes missing. The staff rushes into the storm searching for their lost comrade, but they instead discover that the burial site has been unearthed and the body is missing. With this horrific finding and the strange noises, the staff is unnerved. When the strange noises continue, the staff starts to think something is after them. Faced with an unknown threat, they soon must battle for their lives.