Why did Agatha Christie spend her career pretending that she was "just" an ordinary housewife, when clearly she wasn't? Her life is fascinating for its mysteries and its passions and, as Lucy Worsley says, "She was thrillingly, scintillatingly modern." She went surfing in Hawaii, she loved fast cars, and she was intrigued by the new science of psychology, which helped her through devastating mental illness. So why--despite all the evidence to the...