This study used fNIRS (functional near-infrared spectroscopy) to investigate the neural mechanisms underlying the processing of supernatural fiction, featuring either fictional or realistic characters, compared to real-world stories. Participants' brain activations were recorded while they read supernatural/realistic scenarios. Results showed that reading supernatural scenarios activated sensorimotor and the related frontal regions, compared to reading realistic scenarios. Furthermore, reading supernatural texts with unexpected realistic characters resulted in additional brain activity in the left IFG, compared to reading supernatural texts with expected fictional characters. Mediation analyses indicated that the activation of the left sensorimotor cortex during the reading of supernatural scenarios is mediated by readers' social cognition. Moreover, there was increased functional connectivity among different brain regions within the simulation network, and between the simulation network and the social cognition network, during the understanding of supernatural narratives. These findings suggest that simulation is crucial for readers to comprehend and interpret supernatural stories.