Rational Scrutiny: Paradoxes and Contradictions in Detective Fiction discusses why Chess Hanrahan and Cyrus Skeen, the author's premier heroes and the chief subjects of this volume, are not only extraordinary men of action, but “intellectuals” of the first rank, as well. As Cline writes in the Preface, detective fiction, as a rule, employs both "intellectuals" and "doers". Detectives solve problems; detectives usually do something about them. Problems cannot be solved until they are grasped, understood, and counter actions are identified. In the mystery and detective fiction genres, detectives solve problems that are criminal in nature. Crimes are a consequence of human volition; it is the detective's task to solve them. The problems must first arise before the detective can act. He does not act in a vacuum. He cannot "prevent" problems caused by others, or of which he is not yet aware, because they are products of human volition.

Hanrahan, operating in our own time, and Skeen, acting in the third decade of the 20th century, have their own unique way of approaching crime-solving. Paradoxes do not exist in nature, they observe, nor should they exist in men's lives, values, and actions. Along the way, Cline refutes the common literary notion that some of the best fictional detectives in the past were not "intellectuals" in his essay, "The Wizards of Disambiguation," a critique of the post-modern, deconstructionist school of criticism. He concludes that Skeen and Hanrahan "only partly conform" to Raymond Chandler's description of an ideal detective, except that each abhors “a lively sense of the grotesque”, can express a quick but not necessarily “rude” wit, and harbors a disgust for sham and a contempt for pettiness. And neither is tarnished nor afraid.