Gothic

Gothic is a movie starring Gabriel Byrne, Julian Sands, and Natasha Richardson. The Shelleys visit Lord Byron and compete to write a horror story.
Living on an estate on the shores of Lake Geneva, Lord Byron is visited by Percy and Mary Shelley. Together with Byron's lover Claire Clairmont, and aided by hallucinogenic substances, they devise an evening of ghoulish tales. However, when confronted by horrors, ostensibly of their own creation, it becomes difficult to tell apparition from reality.