In her 1926 essay on "Impassioned Prose," Virginia Woolf declared that Thomas De Quincey was "an exception and a solitary." Subsequent readers have often agreed that he defies categorization. From the beginning of his writing career, De Quincey enchanted and infuriated readers with his paradoxical combinations of reticence and revelation, elegance and slapstick. He was, by his own confession, a hack writer for the periodical press, and yet, even as he chafed against magazine deadlines, he produced a haunting and eloquent prose. His work is in many ways the scholar's nightmare and the writer's dream. Moving from room to room, piling up papers, and revising incessantly, he created a bibliographic labyrinth with sketchy and tantalizing clues. Digressing from his subjects and reworking ideas from various sources, he has evaded scholarly attempts to pin him down neatly and defied Romantic ideas of originality central to his own aesthetic. But readers...