Story in The King In Yellow by Robert W. Chambers. The tale is prefaced with a quote from Bliss Carman's 'Let the Red Dawn Surmise' that holds some similarity to Cassilda's Song: "Let the red dawn surmise / What we shall do, / When this blue starlight dies / And all is through."
Opens in Washington Square where the narrator, Mr. Scott, spots the watchman in the nearby churchyard and feels repelled by him. His model, Tessie Reardon, recounts a recurring dream of a hearse carrying a coffin in which Scott lies alive. He is pleased to learn the church next door is being sold, although upon passing the church one evening the watchman asks him "Have you found the Yellow Sign?".
Tessie gives him a clasp of black onyx with "a curious symbol or letter in gold", which she had found on the day she first dreamed of the hearse. Having injured his hands, Scott finds Tessie reading the King In Yellow, despite not having one in his apartment and having vowed never to read following the tragedy of his friend Castaigne. Sitting down to discuss the play, they realise that the clasp is the Yellow Sign.
They now hear the sounds of an approaching hearse and the watchman, possessed, it seems, by the King In Yellow, enters. Tessie drops dead of fright. The watchman then attacks Scott and seizes the Yellow Sign. When help arrives, they find Scott and two corpses as the watchman had been dead for months...
Interestingly, green plays a minor thematic role in the story: