Laura Skandera Trombley, the preeminent Twain scholar at work today, reveals the never-before-read letters and daily journals of Isabel Lyon, Mark Twain’s last personal secretary. For six years, Isabel Lyon was responsible for running the aging Man in White’s chaotic household, nursing him through several illnesses and serving as his adoring audience. But after a dramatic breakup of their relationship, Twain ranted in personal letters that she was “a liar, a forger, a thief, a hypocrite, a drunkard, a sneak, a humbug, a traitor, a conspirator, a filthy-minded and salacious slut pining for seduction.” For decades, biographers omitted Isabel from the official Twain history at his decree. But now, the truth of the split is exposed at last in a story that sheds light on a lionized author’s final decade.