This essay examines the philosophies of history at work in the narrative conventions governing the presentation of the past in its relations with the present in the analytical and hard-boiled detective story. True to its roots in an Enlightenment philosophy of science, the analytical detective story adopts a teleological view of history, in which the past is narratively positioned in a fixed relation to the present, such that the detective can work backward from the traces of this past that remain in the present, in order to explain the hidden causal principles behind the mystery. For the hard-boiled detective, inhabiting a post-Newtonian universe, the relations between past and present are still open to renegotiation. Caught between the contingencies of the present and the uncertainties of the future, the hard-boiled detective is forced to adopt a less teleological attitude toward the past, which results in the detective becoming a protagonist in the mystery, and placing the detective at odds with the objectivist philosophy of history on which the adversarial criminal trial process is based.