Several of Geoffrey Household’s thriller novels have earned critical acclaim as classic examples of this difficult genre. He sustained a specialized literary tradition identified for a generation after 1900 with such works as Joseph Conrad’s The Secret Agent (1907) and John Buchan’s The Thirty-nine Steps (1915) and Greenmantle (1916). Though Household by experience was a worldly man, the tone of his thrillers is chivalric. His heroes adhere to (or are notable for their deviations from) aristocratic codes of conduct with roots in the eighteenth and nineteenth centuries: personal honor, “playing the game,” respect for or empathy with one’s opponents, individualism, “fair play,” a rather quixotic personal bravery, and a keen appreciation, particularly in moments of danger, of people’s reliance on nature. Avoiding the hard-boiled or socially commonplace characters favored by many authors of his day, Household modernized the nineteenth century’s traditional tales of highly intelligent, educated, and cultivated individualists who became enmeshed in, and successfully met, deadly challenges.