Shakespeare's obsessive interest in syphilis, his clinically exact knowledge of its manifestations, the final poems of the sonnets, and contemporary gossip all suggest that he was infected with "the infinite malady." The psychological impact of venereal disease may explain the misogyny and revulsion from sex so prominent in the writings of Shakespeare's tragic period. This article examines the possibility that Shakespeare received successful treatment for syphilis and advances the following new hypothesis: Shakespeare's late-life decrease in artistic production, tremor, social withdrawal, and alopecia were due to mercury poisoning from syphilis treatment. He may also have had anasarca due to mercury-related membranous nephropathy. This medical misadventure may have prematurely ended the career of the greatest writer in the English language.