Behind the Velvet Screen

In an exclusive 1920s speakeasy, the star attraction was a pianist known only as 'Madame Silence'. She played blindfolded and entirely hidden behind a heavy velvet screen. Patrons whispered she was a horribly disfigured runaway. Arthur, a newly elected and wildly popular Governor, visited the club one evening. Upon hearing her play a hauntingly familiar childhood melody, he broke down in tears and demanded to see the woman behind the screen. Madame Silence hesitated, then slipped a note from underneath: *'If you must. Return tomorrow at midnight, and bring a silver hand mirror.'* Arthur obeyed. When the velvet screen was finally drawn back, Arthur stared at her, dropped the mirror in a shatter of glass, and let out an agonizing scream. By morning, Arthur had abruptly resigned from office, abandoned his entire fortune, and vanished from the public eye forever. What did Arthur see?