In London, the archeologist Anna Ash is informed by her Professor Joan Holland that the excavation site at the Sixteenth Century Ludgate Orphanage, where she is researching the Cult of the Black Priest during the Great Plague, will be demolished on the next morning to contain the contamination since it has been found the Y.pestis in the digging. The stubborn Anna breaks in the building at midnight expecting to find any substantial evidence that could stop the demolition. Meanwhile, four drugged punks hit and run with a stolen car and they hide inside the building. They are haunted and attacked by a ghost and one of them, Clive, is wounded. When Anna stumbles with the hoodlums, she realizes that Clive is contaminated and needs help. But soon they find that they are trapped in the building.