The Brotherhood of Hecate, a secret society of 1660s London, conducted experiments in live tissue creation. What they created broke free, killing scores of Englishmen in the process. Any evidence of the existence of the Brotherhood or their demon spawn was destroyed in the Great Fire of 1666. Now, 170 years later, the Brothers are back and so are their creatures, once again killing Londonites. You take on the role of a demon-battling priest or microbiologist. Your mission is to stop these Nightmare Creatures from killing. Roam the streets of London, killing anything that crosses your path as you search for Adam Crowley, the evil genius who has resurrected the Brotherhood of Hecate. Collect weapons and powerups to aid in your travels.