Stories offer a refuge from people’s mundane troubles and commitments by immersing them in intricate fictional worlds. Narrative transportation, i.e., the feeling of being “lost” in the world of a story, has been found to be an important measure of involvement with narratives (Green & Brock, 2000). Numerous studies have examined the impact of literary fiction on readers’ theory of mind, but the relationship between genre and narrative transportation remains relatively unexplored. Black and Barnes (2015a) proposed that exposure to literary fiction produces higher narrative transportation than exposure to nonfiction texts. The present investigation sought to replicate this finding while (a) measuring baseline trait empathy, (b) addressing a confound of genre and reading difficulty noted in prior work, and (c) assessing the mediating role of affect on the relationship between genre and narrative transportation. Empathy was positively correlated with narrative transportation, r = .39, p < .001. Narrative transportation was higher for participants who read challenging fiction and nonfiction than for participants who read easy fiction, F(2, 891) = 5.79, p = .003, ηp2= .013. Positive affect, but not negative affect, mediated the effect of challenging versus easy text conditions on narrative transportation, b = –.16, se = .04 (95% CI [–.25, –.08]). These findings suggest that narrative transportation may not be dependent on story genre, but rather on a given text’s difficulty level and the positive emotions experienced while reading.