This study examined how seductive details affect on-line processing of a technical, scientific text. In Experiment 1, each sentence from the experimental text was rated for interest and importance. Participants rated seductive details as being more interesting but less important than main ideas. In Experiment 2, we examined the effect of seductive details on reading time and learning. Seductive details reduced the amount of time readers spent reading base text sentences, and hindered recall of important ideas and deeper processing as measured by an essay task. These findings extend previous research [Harp, S. & Mayer, R. E. (1997). Role of interest in learning from scientific text and illustrations: on the distinction between emotional interest and cognitive interest. Journal of Educational Psychology, 89, 92–102; Harp, S. F., & Mayer, R. E. (1998). How seductive details do their damage: a theory of cognitive interest in science learning. Journal of Educational Psychology, 90, 441–434.] to suggest that the negative effects of seductive details’ on comprehension were due to a combination of reduced attentional allocation and disruption of text coherence.