Research suggests that identification with all humanity (IWAH), a socio-psychological basis underpinning global solidarity, may be fostered by science fiction (sci-fi). However, the causality remains undetermined, and the underlying mechanisms are not fully explored. To address this, we propose a genre-specific pathway of self-transcendent media effects and test it from both the immediate and longitudinal perspectives. We conducted three studies with participants recruited from China. The preliminary study ( N = 1,060) revealed that sci-fi was distinctive in its capacity to elicit awe, a nuanced self-transcendent emotion in response to vast and novel stimuli. Using two controlled experiments, Study 1 ( N = 713) found that sci-fi narratives (vs. realistic narratives or no-message) boosted state IWAH by inducing awe. Through a three-wave panel design, Study 2 ( N = 543) documented that cumulative sci-fi engagement elevated IWAH over time by facilitating awe experiences in everyday life.