At his 1992 trial, Jeffrey Dahmer, an alcoholic worker in a chocolate factory, admitted to the murder of seventeen young men during a thirteen-year killing spree. His gruesome full disclosure, including accounts of cannibalism, fired the popular imagination and helped spawn a virtual cottage industry of books, trading cards, movies, and other products. But behind the monstrous ghoul of popular imagination, there lurked a desperately lonely young man whose killings were the result of years of progressive mental illness.

While pregnant with Dahmer, his mother, Joyce, endured a particularly trying pregnancy, suffering extended bouts of nausea and nervousness and strange fits of rigidity. Doctors prescribed morphine and phenobarbital, among other medications. At one point Joyce was taking twenty-six pills a day, immersing her fetus in a soup of powerful depressants. Joyce Dahmer also found nursing to be acutely unpleasant and within a week of Dahmer's...