In 1906, the murder case of Chester Gillette and Grace Brown gripped the nation. Sensational newspaper coverage billed Brown's death as the epitome of a woman wronged. Had Gillette drowned his pregnant lover in order to avoid having to marry her? A jury thought so, and he went to the electric chair. But the essential mystery and drama at the heart of the story remained unsolved. Its appeal to twentieth century popular culture persisted for decades, inspiring a major American novel, a popular Hollywood film, ballads, books, television programs, and endless speculation.

Although they met in a factory, the young Gillette and Brown came from sharply different circumstances. Gillette was the son of formerly successful parents who gave up a hotel and other businesses in order to be Salvation Army missionaries. A prep school dropout bouncing between jobs, the twenty-two year old ended up working in his wealthy uncle's...