In 1916, a young Quaker schoolteacher and poetry scholar named Elizebeth Smith was hired by an eccentric tycoon to find the secret messages he believed were embedded in Shakespeare's plays. She moved to the tycoon's lavish estate outside of Chicago expecting to spend her days poring through old books. But the rich man's close ties to the U.S. government, and the urgencies of war, quickly transformed Elizebeth's mission. She soon learned to apply her...