In some fictional narratives, literary significance resides in two parallel trajectories of signification. They at once contradict and need each other in conveying the thematic message of the text. Going along only one of the two trajectories will result in a partial understanding not only of the thematic message but also of the character images and the aesthetic value of the narrative. The gradual perception of the two coexisting trajectories increasingly complicates the response to the verbal choices in the narrative. Such dual signification is essentially different from previously investigated complicated meanings of literary texts. This essay explores how the same verbal choices take on different degrees of importance and generate conflicting thematic meanings in the dual trajectory of signification in Ambrose Bierce's "A Horseman in the Sky," which forms an implicit yet sharp contrast with the single trajectory in Bierce's "The Affair at Coulter's Notch." Based on the analysis, the essay will discuss how to uncover the dual trajectory which has so far eluded critical attention.