Question: Which event in Edgar Allan Poe's life has remained mysterious, prior to which became engaged to Sarah Elmira Royster Shelton, and was soon found delirious in Baltimore and in need of assistance?
{'answer': 'his death', 'supporting_facts': [['Sarah Elmira Royster', 0], ['Death of Edgar Allan Poe', 0], ['Death of Edgar Allan Poe', 1]]}