Parker, who has a Ph.D. in literature from Boston University, is especially well versed in the detective genre—he focused his dissertation on Dashiell Hammett, Raymond Chandler, and Ross Macdonald— and he is also well aware that this genre has much older roots than those found in the works of Arthur Conan Doyle. The fictional sleuth is merely one of the most popular versions of the hero on a quest, as delineated in Vladimir Propp's seminal Morphology of the Russian Folk Tale (1928), a hero who is often tempted but who steadfastly remains true to his beliefs and his determination to complete the quest. Spenser is clearly a Lancelot figure, and knowing in detail the history of such characters allows Parker to take Spenser out of the mold enough to be interesting but not enough to destroy his deep ties to the genre. In other words...