Mark Twain's fantastical last novel took him twelve years--and three long drafts—to complete. Based on boyhood memories of the Mississippi River Valley and of the print shops of Hannibal, the story is set in medieval Austria at the dawn of the printing craft. It is a psychic adventure, full of phantasmagoric effects, in which a penniless printer's apprentice—a youthful, mysterious stranger with the curious name 44—gradually reveals his otherworldly powers and the hidden possibilities of the mind. Ending on a startling note, this surprisingly existential novel reveals a darker side to the author's genius.

This long-overlooked work appears here as Mark Twain intended it and replaces the bogus 1916 edition published by Albert Bigelow Paine, which relied on the first, instead of the final, draft, deleted one-fourth of the words, added a character, and misrepresented the ending. In addition, for the first time in the Mark Twain Library edition, a glossary of printer's terms is featured along with expert notes and commentary.